The South China Sea and the Maritime Nature of War for 20th Century Vietnam :

The Maritime Nature of the Wars for Vietnam (1945-75)[1]

Christopher E. Goscha[2]

4^th Triennial Vietnam Symposium

Texas Tech University

Vietnam Center

11-13 April 2002

Lubbock, Texas

Introduction

As in a time of peace, so in a time of war: The sea is not always an insurmountable barrier; it can just as easily bridge the gap between two widely separated points. In a time of peace, of course, this is easier to grasp. The oceans can often transport heavy commercial loads faster, more cheaply, and more effectively than overland routes. One has only to think of Fernand Braudel's La Méditerranée to remember how this sea generated commercial, cultural and historical exchanges between Europe and northern Africa, and further.[3] Denys Lombard has shown similar connections in his magisterial study of Java and his studies of maritime trade in Asia.[4] And more research is flowing in this direction.[5] For geographers, the water nature of the latter region comes as no surprise. A quick look at the map makes it clear that the sea links Southeast Asia at the middle, the aquatic bridge between the peninsula extending from southern China to Malaya and the archipelago, reaching from Singapore to the Philippines..[6]

In recent years, excellent studies have focused on the importance of understanding the historical and economic importance of the sea-lanes linking the region before the installation of Western imperialism.[7] Most of this work, however, is concerned with the sea's commercial role in peacetime. Little has been done on the connecting power of the ocean in a time of war in general,[8] and even less on the maritime nature of 20^th century ‘anti-colonial conflicts' against Western powers in particular. This is surprising, since the two major wars in Southeast Asia of the 20^th century – the Indonesian and Vietnamese ones – were profoundly linked to water.[9] Blocking a wider view is the fact that most studies of wars for 20^th century Southeast Asia remain locked into oppositions between “colonisers and colonized”, between “colonialists” and “nationalists”; they tend to favour the diplomatic and political over the geographic and economic; and almost always focus on the land without thinking about how water might fit into the picture.

In this paper, I would like to try to factor the sea into our understanding of the wars for Vietnam in the 20^th century. e Vietnam Wars, and rather than speaking of the wars in Vietnam, I will speak about the wars for Vietnam. ~~The stake was control of the Vietnamese state, but the wars engaged a much wider region,~~ ~~not the~~ ~~least logistical~~ly . ~~I have previously published work~~s ~~on the role of land- and riverbased networks in Thailand, Laos, Cambodia~~ ~~and southern China, and would here like to fit the~~ ~~sea~~ ~~into the picture.~~ ~~However, r~~ My idea is to shift the view of thirty years of war from the land to the sea, from that thin Nation-State we now call Vietnam to the much larger body of water hugging it along the long eastern coastline. In short, our analysis of the wars fought for Vietnam between 1945 and 1975 cannot be limited merely to the Nation-State nor to the land. The term “South China Sea”, like any other geographical term, was invented in order to make sense of an observed geographical reality. The South China Sea refers today to the large body of water in the Pacific Ocean, stretching from the Taiwan Straits in the northeast to merge with the Gulf of Thailand before ending in the southwest at the Straits of Malacca. The Philippines and Borneo constitute its eastern border; the northern islands of the Indonesian archipelago its southern frontier; while the eastern Vietnamese coast blends with southern China via Hainan to make up its western boundary. Viewed from this wider perspective, one can see that Vietnam is part of a larger maritime world, located between East and Southeast Asia and linked by maritime routes and a long coastline running from southern China to the Gulf of Thailand, and further. This question of what links space in a time of war is also worth bearing in mind when studying the thirty year war for Vietnam. Rather than conceptualising wars from “on high” in strictly diplomatic or political terms, I would like to argue that it is equally important to think about how the maritime nature of the wars for Vietnam were linked “down below” and across seemingly impermeable national borders. Geography, goods, sailors and ships will thus count as much as diplomacy, military strategy, and heads of state. The two go together.

The Outbreak of War

When the “Viet Minh”, the well-known Vietnamese nationalist coalition led by the Indochinese Communist Party (ICP), took power in August 1945, the economy was in a wreck, much of the northern peasant population was starving to death, the army was nascent, and the state was weak. The presence of around 100,000 Chinese nationalist troops in Vietnam north of the 16^th parallel from late September 1945 until mid-1946 only aggravated an already explosive situation.[10] In the south, the British allowed a rapid French return and by late September hostilities between the French and the Viet Minh had already begun over the future leadership of Vietnam. The Vietnamese wanted independence; the French sought to reassert their pre-war colonial presence in mainland Southeast Asia, lost to the Japanese in March 1945. To that end, the French armed forces re-took Saigon and reoccupied provincial towns, routes and bridges, pushing the Viet Minh into the densely forested marshes and canals of southern Vietnam. Hardly a year later, in December 1946, Franco-Vietnamese negotiations degenerated into full-scale war in all of Vietnam. In February 1947, pushed out of Hanoi, the central government chose to operate from the highlands of Thai Nguyen and Tuyen Quang provinces near the Chinese border. Full-scale war had broken out in Indochina over the control of Vietnam. It would take thirty years of fighting to determine the outcome.

Under communist direction, the Democratic Republic of Vietnam (DRV) operated from the hills of northern Vietnam until the end of the war in 1954. The country was divided into administrative and military inter-zones (lien khu (LK)), falling within the three major geographical divisions of Vietnam: the North (Bac Bo), the Centre (Trung Bo) and the South (Nam Bo). Each one looked out over the South China Sea and shared an overland border with Laos and/or Cambodia. In Nam Bo, the Viet Minh operated mainly in the coastal and marshy areas running from Ca Mau to Ha Tien (LK 9) to Thu Dau Mot and Bien Hoa provinces (LK 7). The situation was better in Trung Bo, where French land forces never reoccupied vast regions of Thanh Hoa, Nghe An, and Ha Tinh provinces in upper central Vietnam (LK 4) and Quang Nam, Quang Ngai, and Binh Dinh provinces in lower central Vietnam (LK 5). However, the French navy and air force held on to the major ports of Nha Trang, Hoi An, and Hue, but not to Tuy Hoa, Tam Quan, Thanh Hoa, Vinh (Cua Hoi) or other, smaller openings to the South China Sea. Geographically, battles and strategy during the Franco-Vietnamese war included all of Vietnam, and even western Indochina (Laos and Cambodia). Before 1954, there was no entirely independent Vietnamese state to serve as a rear area for fighting elsewhere in Vietnam. And until the Chinese communist victory and occupation of Guangdong, Guangxi, Yunnan and Hainan Island in 1949-50, all of Vietnam was isolated from large-scale external military and financial aid.

As for communications, because of Vietnam's thin, S-like shape on the eastern edge of the Indochinese peninsula and French domination of the major roads until the early 1950s, the Vietnamese and Chinese coastal junk trade became one of the most important ways by which the DRV conducted its commercial exchanges both inside and along the country's coastline. French air superiority meant that much of the Viet Minh's trade movements had to go under the cover of the night.[11] Junks and sampans supplied rice-deficit regions in lower Trung Bo and LK 7 with paddy exported from Viet Minh-controlled parts of the Trans-Bassac in Nam Bo. Central Vietnam exported locally made arms up and down the coast. During the northeast monsoon season between November and April, traffic sailed from the north to the south, while the southern monsoon lasting from May to October moved vessels towards the north. In the Gulf of Tonkin and the Gulf of Thailand, exchanges went in both directions thanks to the increasing numbers of small motorised junks and favourable winds. The profoundly aquatic nature of the southern and northern deltas, if not the entire coastline, made sampans a vital part of the Viet Minh's internal exchanges coming from the South China Sea.

The South China Sea in a War of Decolonisation[12]

The South China Sea was a link for the Vietnamese in a time of war, but not always an easy one by the very fact that it was war. During that brief moment after the Japanese defeat in August 1945 and the outbreak of full-scale war in all of Vietnam in late 1946, the DRV did its best to restart trade via the South China Sea. Northerners initiated exchanges with southern Chinese traders, while southerners turned to Southeast Asian markets, in particular Thailand. Those in central Vietnam looked to both Southeast and East Asia. Southerners attempted also to tap into the Chinese junk trade in the South China Sea; but this would turn out to be extremely difficult for all the war against the French.

Until December 1946, the DRV's opposition to the French mirrored what would happen against the Americans two decades later. The DRV continued to exist territorially above the 16^th parallel, while a war raged south of that line against a foreign power opposed to the reality of that northern state's claim to Vietnam. From September 1945, the DRV in the north used junks and sampans to send hundreds of young men of the Nam Tien (Go South) units to fight the French in Nam Bo.[13] Located strategically in lower Trung Bo, zone 5 played a particularly important role in channelling arms, gold, and medical supplies to the south. Ancient coastal navigation lent itself well to clandestine arms infiltration. Sampans, small junks, and fishermen helped shuttle these goods to the south. In late 1946, one of the first coastal missions to Nam Bo delivered 500 rifles, 1,000 grenades, eight Thompson guns, and two heavy machine guns among other things.[14] These coastal links remained vital after the outbreak of war in all of Vietnam, especially since LK 4 and 5 tended to remain unoccupied. In early 1947, one of the DRV's best known spies, Pham Ngoc Thao, organised a secret water route to supply Nam Bo with supplies, medicines, information, and above all 20 kg of gold and French Indochinese piastres, vital to Nam Bo's capacity to buy arms and supplies in French-controlled and foreign markets.[15]

Unlike the war against the U.S., Vietnamese opposed to the French could also use the South China Sea to reach clandestine arms markets deep in Southeast Asia. This was particularly true for southerners. In 1946 or 1947, for example, the ICP's southern territorial committee (Xu uy Nam Bo) sent Duong Quang Dong to Kuala Lumpur to receive several tons of arms donated by the Malayan Communist Party. Dong successfully delivered these arms to Nam Bo via the sea, marking one of the first long-distance missions in DRV maritime logistics.[16] Southern and central Vietnamese exchanges with Thailand were, until around 1951, of even greater importance.[17]

The Viet Minh located along the coast of Trung Bo (LK 4 and 5) relied most heavily on the South China Sea and Chinese traders in order to conduct their coastal exchanges and to reach markets in Beihai (Pakhoi), Macao, Hong Kong, Canton and the island of Hainan. Already in mid-1946, the DRV had approved formation of a semi-official Import-Export company called the Viet Thang – the “Vietnamese Victory Company”. It administered LK 4 and especially LK 5's external trade with Hong Kong, Macao, the island of Hainan, and, to a lesser degree, Beihai. LK 4 worked also through similar, though smaller, trading companies in Vinh, Thanh Hoa, Diem Dien, and Quat Lam to trade with Haiphong and especially Beihai via Cat Ba (see below). Central Vietnamese traders had little choice but to rely on maritime Guangdong as their major overseas trading market and perhaps the Philippines located straight to the east.

The Viet Thang had first been created by the short-lived Tran Trong Kim government installed by the Japanese in mid-1945. Following the defeat of the latter, in 1946 the DRV restarted this company with five million French Indochinese piastres. It served as a crucial relay in moving food supplies, arms and soldiers from the north to the south, and vice-versa.[18] At the outset, this trading house was fittingly placed in the ancient Vietnamese trading town of Hoi An (Faifoo). Until the outbreak of war in northern Vietnam in late 1946, it had subsidiaries in Hanoi, Hue, Da Nang, and Vinh. With the return of the French in force to these ports in early 1947, the centre of the Viet Thang was transferred to Tam Quan in Binh Dinh province, with at least four branches operating in Quang Nam, Quang Ngai, Binh Dinh and Tuy Hoa, each with smaller agencies scattered in the countryside for distribution and buying purposes. Because the French Expeditionary Forces focused on the two deltas of Vietnam, these central zones could operate more freely from direct French ground force interference, other than short-lived, if very destructive, aero-naval attacks. In any case, it appears that the Viet Thang was never shut down. As of 1950, it still maintained a total capital of ten million Bank of Indochina piastres.[19]

The Viet Thang was not an official part of the Vietnamese Navy. Indeed, a Vietnamese navy did not yet exist (see below). While the DRV government did its best to direct this company's actions, the evidence available suggests that the state was relying on private Vietnamese and Chinese traders to conduct its wartime commerce. If authorities bought 2/3 of the Viet Thang's merchandise at the official price, they allowed local, private traders to sell the remaining third of their imports at the higher, unfixed market price.[20] However, Viet Thang traders were no doubt happy to have local state authorities allocate them the lion's share of all trade in the Viet Minh zones, given long-established and competitive Chinese operations in Vietnam. In any case, in 1949 a French naval intelligence officer claimed that the Viet Thang had “established a monopoly” on the Viet Minh's foreign trade in Trung Bo.[21]

Based in Tam Quan, the Viet Thang's two main foreign destinations in the South China Sea were Hong Kong and Macao. Through their local agents and connections reaching into the interior, the Viet Thang located, purchased, and transported sought after exportable products to the coast. With little hard currency for purchasing foreign imports, the Viet Thang did its best to amass valuable exports such as opium, cinnamon, sugar, shark fins, silk, tin, areca, paper and various delicacies appreciated in Chinese markets.[22] Cinnamon, opium, paper and tin dominated its exports. In September 1949, the Viet Minh at Quang Ngai used a 70 ton junk to export 40 tons of tin.[23] In August 1950, the French navy intercepted a junk carrying four tons of cinnamon and another loaded with 20 tons of this spice as well as three tons of tin.[24] Arms, medicines, pharmaceutical products and some petroleum products were the Viet Thang's major imports from southern China.[25]

Southern Chinese ports offered central Vietnamese potential access to arms, equipment, and goods coming from the interior of China, Asia and the West in the wake of WWII. Second, these ports were important relays in international smuggling operations that targeted the ‘emerging markets' offered by escalating war in China and anti-colonial versions in Indochina and Indonesia. Third, in the wake of WWII, large amounts of Japanese and Allied surplus arms, ammunition and military equipment escaped destruction or confiscation to feed an impressive Asia-wide arms market channelled through these ports. Besides its inland Chinese sources, Macao and Hong Kong were also important transit points in the smuggling of large amounts of Allied arms from the Philippines towards the shores of mainland Southeast Asia. Fourth, the free port status of Macao and Hong Kong in the late 1940s made them particularly attractive destinations for acquiring all sorts of Western medicines, acids, petroleum products, radio equipment, and replacement parts. Fifth, the Viet Minh opened secret bank accounts in these commercial sites and conducted an important part of its piastre trafficking thanks to Chinese banking connections there. Sixth, these ports were often the home of many of the ethnic Chinese traders dealing with the Viet Minh in Vietnam .

In Macao, the Viet Minh could enter into contact with a variety of traffickers; especially those specialized in selling left-over Allied arms. A French naval study of this traffic concluded that the availability of WWII war materiel from China on the Macao black-market was at its height from late 1946 to the end of 1947.[26] Arms from the Philippines probably filled the gap thereafter. In January 1948, French naval intelligence reported that Viet Minh agents had been sent to Macao to take possession of a large quantity of mercury and arms coming from “the Pacific Islands” worth a total of five million Hong Kong dollars. A Chinese crew was to deliver it to the region of Vinh.[27] The French navy claimed that motorized junks left Macao two times a month to deliver American arms and equipment and Chinese and Western medicines to Quang Ngai and Quang Nam provinces, suggesting the LK 5 was more closely linked to Hong Kong and Macao than to Beihai. In return, they took stocks of opium, cinnamon, sugar, textiles, silk and Bangka tin to southern China.[28]

This low-level South China Sea semi-private war trade was not large enough to make a strategic difference in the war against the French; however, it did help the Viet Minh hang on in difficult circumstances, especially in central Vietnam. In April 1949, LK 4's Minh Duc trading house relied on a Chinese ship owner from Beihai to deliver seventeen tons of war materiel and supplies.[29] In Thanh Hoa, the Lien Hung company combined Chinese traders and the Viet Minh police to move goods to and from Beihai.[30] In 1948, Viet Minh documents revealed that Quat Lam had been receiving monthly quantities of 2,000 bales of cotton, one ton of mercury, 100 kg of potassium chloride and small quantities of mortars and bazookas from Beihai.[31] Even in even the worst of times, a Viet Minh customs agent in Quat Lam still declared that “a dozen” junks continued to arrive every month.[32] In 1950, the French claimed that despite their efforts to stop this clandestine trade, the Viet Thang in particular continued, “thanks to their extreme prudence”, to maintain “fairly regular” trading relations with the exterior.[33] Whatever its weaknesses (and there were many), the Viet Thang is an important historical example of how the South China Sea began to play itself out in a mainland 20^thcentury war for Vietnam.

Chinese Maritime Networks and the War for Vietnam

While the Vietnamese were most certainly players in the DRV's junk movements running up and down the eastern side of the Indochinese peninsula, the evidence suggests that bigger Chinese junk traders played the dominant role in arranging and transporting LK 4 and 5's goods to and from southern China.[34] Indeed, during the war of decolonisation against the French, the Vietnamese had to tap into age-old Chinese trading networks in order to administer their trade via the South China Sea. Chinese business operations based in Beihai were particularly engaged in trade with upper Trung Bo. In control of several local munitions and arms factories in the Beihai area, “twenty or so important Chinese traders, with perfect knowledge of Tonkin and northern Annam”, dominated “almost all of the traffic” with LK 4. Chinese merchants in Beihai traded mainly with the Viet Minh ports of Thanh Hoa, Vinh, Diem Dien, Thai Binh, and Phat Diem, all small port-towns linked profoundly to the Vietnamese interior by a myriad of waterways. Viet Minh customs agents and the Beihai Chinese merchants monitored as meticulously as possible their shipments across the Gulf of Tonkin by radio. Departure and arrival lists were carefully compared, undeclared goods were seized, and receipts were mandatory. The DRV paid in Indochinese piastres, gold, cinnamon, tin and/or opium. Ho Chi Minh banknotes and dong were worthless in this trading world.[35]

Both the Indonesians and Vietnamese needed these Chinese business networks precisely because of their regional nature and long-distance maritime connections. To ensure their economic cooperation, the Viet Thang accorded the Chinese “many privileges”, according to one of the company's former employees.[36] In early 1948, the Chinese trader, Yui Chinh Chuy (Cam Phuc) informed LK III officials that he had formed a new Import-Company, Phuc Thinh, in Diem Dien to transport DRV goods.[37] DRV documents reveal that Chinese traffickers, such as Yeung Tin Wan and especially Woong Tac Mao, were deeply involved in running arms and explosives to the Viet Minh in upper Trung Bo from Beihai.[38] The former president of the Chinese congregation of Cat Ba used several of his 20 to 40 ton junks to smuggle goods from Beihai to upper central Vietnam.[39] In Bong Son, Chinese traders in April 1946 had acquired twenty tons of tin for export further north, but were held up by the DRV government seeking to take over this trade.[40]

The Hainanese form an interesting Chinese link in the South China Seas. To this day, the Hainanese community of fishermen living on the island of Dao Bach Long Vi in the Gulf of Tonkin between Haiphong and Hainan speak Vietnamese and continue to trade with central Vietnam. (The island was once disputed between China and French Indochina, but has since been recognised by China to be under Vietnamese sovereignty.) The Hainanese living or active in central Vietnam bought forest products, precious stones, cinnamon, swallow nests, tiger pelts, elephant tusks from as far inland as Laos in order to introduce them to the international market via the South China Sea. Hainanese junk traders had long been particularly involved in the cinnamon trade with central Vietnam.[41] This continued to be the case in a time of war. The Hainanese trader, “Cao Vinh Sanh”, was said to run trading missions for Trung Bo authorities; he was also a well-known cinnamon trader at Tam Ky.[42] There were also large Hainanese communities residing in Rach Gia and Kampot provinces off the Gulf of Thailand. Hainanese merchants there played an important role in running the southern resistance's lucrative pepper trade with Bangkok. A recent Vietnamese study reveals that between 1950 and 1953 the Viet Minh generated around thirty-three million piastres from its pepper trade via the Chinese in southern Indochina.[43]

As for Hainan, repeated interceptions, captured documents and radio decrypting proved that a “regular” trade existed with the Viet Minh in Trung Bo. In March 1948, for example, a large junk transporting materials and Chinese medicines to the Viet Minh from Hainan was captured.[44] Following Pibul Songkram's return to power in Thailand in 1948, Vietnamese communists working there hoped to shift their Southeast Asian trading routes from Thailand to Hainan in order to continue to supply the southern resistance which was increasingly isolated from external supply sources. However, in 1948, one of the highest ranking Vietnamese communists in the ICP, Cao Hong Lanh, reported to his colleagues in Thailand that establishing a junk route with Hong Kong and Hainan would be difficult given that the GMD controlled the western half of Hainan facing Vietnam.[45]

Of course, trade could have improved when Chinese communists invaded the island in April1950. Indeed, the DRV hoped that Hainan would provide a new maritime way of supplying central and especially southern Vietnam, which would remain cut-off from direct, overland aid from the CCP in the north.[46] In August of that year, a Chinese merchant captured by the French explained that he had participated in this traffic between Hainan and central Vietnam because of the “important profits” to be made. He had transported 6.5 tons of red sugar, 3.5 tons of cinnamon, and 6.5 tons of swallow nests among other things for the Viet Minh of Quang Ngai. The DRV wanted in exchange pharmaceutical products and textiles.[47] The mission was intercepted.

Running such large loads against the French navy was obviously extremely risky, especially when the CCP victory in 1949 led the French to tighten their naval surveillance of the Gulf of Tonkin and the western waters of the South China Sea.[48] On November 3, 1950, intercepted southern Viet Minh radio communications explained that the time was not yet ripe for sending large numbers of junks to Hainan.[49] French surveillance was also sufficiently effective to frustrate the Vietnamese hope of supplying central Vietnam by air from Hainan. In August 1950, LK 5 reported that an airbase had been prepared to receive supplies at a secret site in Quang Ngai. LK 4 had even established a supply office in Hainan.[50] Knowledge of this led the French to step up their surveillance of such locations.

The Paracels were potentially important. The DRV hoped that Chinese communist control of the Paracels could aid in the supplying of southern Vietnam and orders were issued to this effect.[51] However, the evidence suggests that supplying from these scattered islands never really amounted to much.[52] Chinese merchants working for Vietnamese traders or authorities made some use of them. Vietnamese use of the Paracels would increase during the war against the Americans, when the DRV created a small navy and a much more effective naval blockade would push the Vietnamese away from the coast and further into the South China Sea (see below).

Ethnic Chinese networks in Vietnamese ports were also internal openings to the South China Sea, even if the Viet Minh did not administer them directly. In his general economic plan for Saigon-Cholon in 1947, Kha Van Can, the head of the Nam Bo resistance economy at the time, explained that Viet Minh agents were heretofore authorized “to sell [Viet Minh] products directly to Chinese traders.” These traders, he explained, would then transport Viet Minh goods to “agents abroad”.[53] A recent history of the DRV's arms industry during this period confirms that Chinese traders in southern Vietnam helped the Viet Minh import much needed goods from the French zones and even as far away as Hong Kong.[54]

Significance of the DRV's Early South China Sea Trade

But just how important were these commercial exchanges to the DRV? Without access to trading records, it is impossible to say with certainty. According to a captured DRV document, for 1949, 27 transportation junks moving from LK 4 to 5 made their trip successfully for every 24 junks lost to the French. Out of a total of 213,068 kg of merchandise sent by the maritime route, 100,429 kgs or around 100 tons of material and food supplies arrived safely.[55] Of course, it would be absurd to extrapolate from this one document for all the Vietnamese external trade or even the coastal trade. Moreover, 100 tons for one year is not a particularly large quantity. The cargos remained limited in size and vulnerable to French surveillance (Trung Bo's junks averaged in size between one and five tons).[56] We have no figures on the extent of the DRV's long-distance commerce across the South China Seas.[57] Indeed, one of the major maritime differences between the French and American periods was that until 1950 the DRV had no access to modern and powerful arms coming from China and the Soviet Union. Early DRV commerce in the South China Sea was linked to questions of mere survival, not supplying major offensives. Though important, arms were not the major imports. Rice and medicine were. Short-distance coastal routes dominated, not long-distance ones. And Chinese networks counted as much as Vietnamese ones; indeed, the two overlapped.

Although the state may have tried to control operations like the Viet Thang, the DRV never had a Navy or even a merchant marine capable of supplying the war effort directly. That is not to say that the DRV did not try. Emboldened by the Chinese communist victory and concomitant Chinese military assistance, the DRV General Staff under Vo Nguyen Giap outlined plans with Chinese advisors to administer a maritime supply route from Hainan to Trung Bo in order to outfit one entire division and an anti-aircraft battalion by early 1951. This plan probably explains the increase in French naval interceptions from Hainan at this time (see above). Sino-Vietnamese plans were even being made to supply southern Trung Bo and Nam Bo from the sea, though they were apparently never implemented. In any case, the CCP victory had opened the possibility of running a new and effective maritime supply route to middle and southern Vietnam. On 5 September 1949, the General Staff created a “Naval Studies Section” to begin work on creating a Navy, training officers in coastal and astronomical navigation, and developing maritime supply operations between south-eastern China and eastern Vietnam. A special naval unit, “Company 71” was sent to south-eastern China in 1950-51 to undergo intensive training. However, Chinese knowledge of modern naval techniques was spotty at best. Other than the taking of Hainan in April 1950 (thanks to local Chinese fishermen), the Chinese provided little modern naval training to the Vietnamese.[58] In fact, the Vietnamese sent to south-eastern China learned more about land combat than naval warfare.[59]

Nevertheless, back in Vietnam, Company 71 would begin efforts to open water routes between southern China and Hainan to the Bay of Ha Long and central Vietnam; but again the results were very limited. While limited in size, the French navy was not a push-over. The main Chinese supply lines going to Vietnam remained overland ones. The DRV's maritime supply movements were largely private affairs, not part of the armed forces. As late as 1954, a Soviet ship apparently involved in repatriating southern troops to the north docked in the Ong Doc river estuary in Ca Mau. It delivered six tons of guns and ammunition pre-packaged in crates for secret stockpiling for later use. A Soviet vessel had probably made the first major arms delivery to southern Vietnam via the South China Sea in post-colonial Vietnam in late 1954.[60] It also marked the appearance of a Soviet naval presence in Southeast Asia in the 20^th century.

The absence of a Navy would change once the DRV was able to create its state north of the 17^th parallel and war with the Americans became ever more likely. It would also see a fall in the DRV's reliance on Chinese traders as the risks became just too great to justify trying to run the American blockade and trust and secrecy became absolutely vital for transporting Soviet and Chinese arms southwards.

The CCP Victory and the Shift in Logistics in an Emerging Cold War Context

What is important to recall at this point is that the emerging water routes never existed independently of the overland ones, or vice-versa. This was true since the beginning of the war in 1945. Conceptually and historically, the coastal routes linking northern and southern Vietnam against the French are significant. Both French naval intelligence and recent Vietnamese communist publications confirm that a North-South supply route running between zones 4 and 5 to zones 6, 7 and 9 in the extreme south had been secretly called the Ho Chi Minh liaison road (Duong lien lac Ho Chi Minh).[61] Besides arms and supplies, this route also moved important cadres back and forth, ensured vital communications, and strengthened the leadership of the northern-based Central Committee over the southern resistance.[62] The supply route feeding the resistance up and down the Vietnamese coast existed thus long before the overland route of the same name (see below).

The Chinese communist victory of 1949 and the advent of the Cold War in Southeast Asia in 1950 increased the importance of this North-South coastal link. The CCP decision to aid the DRV war effort, under ICP direction, provided northern Vietnam with a key rearguard. Concretely, it linked Bac Bo to the southern Chinese provinces of Yunnan and Guangxi by overland routes, especially after the combined Sino-Vietnamese defeat of the French Expeditionary Corps at Cao Bang in 1950. Although initial Vietnamese military plans in 1949-50 aimed to liberate the Sino-Vietnamese border all the way to the Gulf of Tonkin, the French blocked it and the Chinese Red Army never tried to run its major supply operations to the Vietnamese army via the South China Sea from Hainan and Guangdong province. The French Navy was preparing for such an eventuality[63]; the Americans would have probably intervened; and a smaller and less modern Chinese navy was still more preoccupied with taking Hainan and preparing for the invasion of Taiwan.[64] The decisive battles in the defeat of the French occurred along the Sino-Vietnamese frontier and in the mountainous region of Dien Bien Phu from late 1953 to May 1954, not at Haiphong, Vinh Yen or Moncay. Significantly however, by 1951, an overland trail had been pushed southwards from China, along the western side of the Tonkin Delta, to supply Chinese aid as far as LK 4 and 5. Without this interior route coming from southern China via Bac Bo's western side, central Vietnam would never have been able to supply its impressive main force divisions (which the General Staff had initially hoped to outfit via the Hainan maritime route). These central divisions appeared only in this region from 1951.

However, no division ever existed in Nam Bo during the war against the French. While General Nguyen Binh, the southern commander, had done remarkably well in creating a series of main force battalions, with supplies coming from Thailand, down the South China Sea coast from LK IV and V, and from French-controlled markets like Saigon-Cholon, he could not obtain the heavy armament and large amounts of food and medicines needed to support division-level units. Indeed, if Vietnamese communists in the north were thrilled to receive thousands of tons of military and food aid after the border port of Cao Bang was opened[65], southerners found themselves suddenly in a perilous position as the CCP victory in the north led the U.S. to increase its commitment to Thailand and the French-backed Associated-States of Indochina, the direct competitors to the ICP's revolutionary states. Not only did southerners loose their overland and overseas access to Thailand as Pibul moved towards the U.S., but they also faced tightened French naval surveillance, with American support. An important effect of this was that southern strategists were forced to turn to the inside in order to hook up with the overland trail dropping down from China into LK 4-5 and to double their coastal Ho Chi Minh route with an overland one in the event that they lost access to the South China Sea.

General Nguyen Binh reveals this in his study of the creation of an overland “Indochinese Trail”. His report to the Ministry of Defence in 1951 left no doubt that the creation of this new overland “route crossing all of Indochina” from LK 4 via southern Laos and north eastern Cambodia would allow the Vietnamese to supply Nam Bo “once the Ho Chi Minh liaison route presently doubling route no. 1 is blocked”.[66] The famous Ho Chi Minh overland trail crossing all of former French Indochina – allegedly created in 1959 – clearly got its start, at least conceptually, a decade earlier, at the Cold War conjuncture of 1949-50.[67] It was in response to the Chinese communist victory and the real threat of increased U.S. intervention in Indochina by sea and overland from Thailand. Nguyen Binh was very much aware of what U.S.-led forces had done in Korea since June 1950. Looking at the situation from deep inside Indochina (north-eastern Cambodia to be exact), he predicted that if the war widened and the U.S. entered it against the Chinese and Vietnamese, then the weight of the conflict would shift rapidly to southern Vietnam. French and possibly US forces would then occupy southern Vietnam and Cambodia and Indochina would be cut into two halves.

We must find the means to deal with the situation in which the French enemies increase their armed forces in order to consolidate their hold over the southern zone. We must take defensive measures in preparation for the outbreak of the 3^rd world war and when Indochina will become the principal front in Southeast Asia. French forces could isolate the northern zone from the southern one.[68]

It was in this larger regional and international reading of the war that Nguyen Binh insisted that the “Indochinese Trail” had to be created. Nguyen Binh's worst fears would come true of course a decade later, as the Americans entered the war and made every effort to isolate southern Vietnam from its northern half by sea and land. In this longer durée and wider geographical analysis of the wars for Vietnam, it is not surprising that the famous overland Ho Chi Minh trail began first as a supplement to the maritime routes in the South China Sea, and was then pushed inwards as an Indochinese overland trail following the Chinese communist victory in the north. Land and sea routes are linked in a time of war, just as in a time of peace. To see only one – and not the other – is to miss the picture, and the point. The overland Ho Chi Minh Trail did not appear in 1959 ex nihilo. ~~It has a past both in time and space. Most important, however, is the need~~ ~~<repetition>~~

The Limits of the Overland Routes to Nam Bo

The French colonial withdrawal from northern Vietnam in 1954-1955 and southern Vietnam in 1956 did not bring peace to the region. Five years after the Geneva Conference of 1954 had effectively divided Vietnam into two states with a line of demarcation and a demilitarised zone (DMZ) at the 17^th parallel, tensions rose between the communist-led DRV north of that line and the anti-communist Republic of Vietnam to the south. The president of the south, Ngo Dinh Diem, was a fiercely anti-communist nationalist. Backed by the Americans, this Catholic Vietnamese had already begun to crackdown on any opposition to his power, especially from remaining communist networks in Nam Bo.[69] The DRV was communist and had been anything but happy about Diem's cancellation of the national elections which the Geneva Conference had scheduled to take place in 1956. This made it impossible for Hanoi to proceed towards national reunification through non-military means and allowed the U.S. to replace the French militarily. Backed by the initially ~~t first~~ reluctant communist giants of China and the USSR, Hanoi would approve the decision of its southern branch to abandon political struggle in favour of armed action against Diem. By 1959 armed struggle had resumed below the 17^th parallel under the direction of the southern bureau of the Vietnam's Worker's Party, the “Territorial Committee of Nam Bo” (Xu Uy Nam Bo).[70] It relied on former Viet Minh troops from the “anti-French period”, returning forces which had been regrouped to north Vietnam after Geneva, cadres sent from the north, and worked in collaboration with a newly formed “National Liberation Front” (NLF) under increasingly direct communist control.[71] Later regular troops from the People's Army would be sent south to fight.

The situation was further complicated by the fact that this brewing civil war for Vietnam was no longer occurring within a colonial context; but rather it was increasingly subsumed by a larger and more dangerous Cold War, which had made itself felt in the region since 1949-50.. By the early 1960s, in the heat of such intense Cold War battles as the Berlin and Cuban Missile crises, the Kennedy administration increased the American military commitment to the Republic of Vietnam (RVN) in order to stop perceived Sino-Soviet communist expansion into Southeast Asia. Despite their differences, Nikita Khrushchev's Soviet Union and Mao Zedong's China provided massive quantities of supplies and military aid to the DRV in her battle against the RVN and the American forces coming to her aid. The Chinese, we now know, sent thousands of troops to work for the DRV and 25 years of Chinese military aid was crucial to the DRV's success in reunifying Vietnam in 1975.[72]

For the DRV, the resumption of the war for southern Vietnam meant supplying it from the north. Just as China had played a crucial role in helping the Viet Minh dislodge the French in 1954, now Bac Bo would have to do the same for the south (with military aid from the USSR and China). In May 1959, picking up in many ways where Nguyen Binh had left off in 1951, the DRV began work on creating a functional overland logistics route to supply southern Vietnam via both sides of the Annamese cordillera (Truong Son for the Vietnamese) and by sea. Such routes would ship medicines, weapons, supplies, cadres, and troops to the south. To this end, on 5 May 1959, the Central Committee of the Vietnamese Workers Party[73] (VWP) and its General Staff ordered Senior Lt. Colonel Vo Bam to form the “Special Military Operations Corps” (Doan cong tac quan su dac biet), which was shortly renamed Doan 559. It was led by Vo Bam. Under the party's direction, 500 people worked in Group 559 at the outset.[74] In August 1959, 559's 301^st Battalion (soon renamed Group 70) delivered Western-made weapons to Quan Khu 5 (“Military Region” or MR) for the first time. By the end of 1959, around 50 tons of weapons had been delivered there.[75] In order to push routes to the western side of the Truong Son into lower Laos, on 12 September 1959, the Ministry of Defence and the Central Committee's “Military Commission” (Quan Uy Trung Uong) created Group 959. It became the DRV's specialist team for operations in Laos and worked to ensure supply routes to Nam Bo through Laos.[76]

In July 1959, as part of this search for logistics links to the south, the DRV ordered a simultaneous investigation of possible maritime routes. Battalion 603 began studies of the Gianh River in Quang Binh province, going undercover as group of fishermen. By late 1959, battalion 603 had created a unit of 12 five- to seven-ton vessels for sea operations.[77] However, none of this was easy. In April 1960, the entire programme was dissolved and maritime operations were transferred to the Office of the Navy (Cuc Hai Quan).[78]

Similar difficulties confronted the creation of overland routes. They could not be magically completed and extended to lower Nam Bo in a matter of months or even years. In the early 1960s, groups 559 and 959 had very little success in creating operational trails via the western side of the Annamese Cordillera and Laos. For one, RVN and Lao defences were there. Physical geography and disease alone made transportation overland arduous, dangerous, costly and slow.[79] International agreements, not least of all the Geneva Accords of 1954 and another set on Laos in 1962, made it illegal, theoretically, to violate the territories of the existing states. French Indochina no longer existed as a legal and diplomatic entity. The communists were now operating in a divided Vietnam battlefield; expansion into Laos, Cambodia or even Vietnam below the 17^th parallel could be interpreted as a violation of national sovereignty and could provoke international and military reactions.

While the DRV never really respected rules banning operations in western Indochina, especially in lower Laos,[80] in the early 1960s they had to conduct their secret supplying of the south with the utmost secrecy and on a limited scale for fear of provoking direct U.S. intervention. In April 1961, the Party's Military Commission renewed its efforts to supply southern Vietnam by launching what it called “Operation or Task B” (cong tac B), “B” referring to “Nam Bo”. General Hoang Van Thai ran this programme. He relied on 559 to reach Nam Bo by both sides of the Annamese Cordillera. This was probably linked to the Politburo's approval in February 1961 of a second five year military plan for 1961-1965, calling for the creation in southern Vietnam of armed forces totalling 10-15 “strong regiments”.[81] However, the RVN and the Lao government combined efforts to maintain control of their territory bordering the DRV (especially MR 4). Their efforts were particularly effective in 1962 and 1963. As a result, 559's overland routes only scored very limited successes in the early 1960s. Again, the trails remained very primitive and irregular; the terrain was inhospitable; and enemy surveillance and ripostes a reality.[82] From November 1960 to April 1961, 559's Group 70 delivered only 30 tons of weapons to areas near the DMZ. For all of 1961, 559 only attained 50% of its supply goals, including 317 tons of weapons. From November 1962 to April 1963, regiments 70 and 71 delivered to southern junction points 36 tons of weapons, 47 tons of rice, and brought 100 cadres out of Nam Bo.[83] These are not particularly large amounts and they were never delivered far below the DMZ. Moreover, during this same period, attempts to run an overland trail down the eastern face of the Annamese Cordillera remained blocked.[84]

The Water Nature of the DRV's War against the U.S. and the Republic of Vietnam

Viewed from this wider perspective, the serious difficulties in extending the Truong Son routes forced the DRV to turn to the sea. The diplomatic dangers of running through Laos reinforced this (though attempts to move through lower Laos had already begun). Moreover, in the early 1960s, U.S. naval surveillance of the western part of the South China Sea was still relatively limited (the threat of war over Taiwan had been real between 1954 and 1958, while the Berlin and Cuban crises deflected U.S. strategic and naval attention elsewhere) and the Republic of Vietnam's navy was experiencing serious growing pains. It was possible to run large loads of modern arms without being detected.[85] Although early attempts to send supplies by sea to the south had begun in July 1959, it was not until the Ministry of Defence formed Group or Doan 759 (backdated for “July 1959”) on 23 October 1961 that Vietnamese communist efforts to supply the south with modern Chinese and Soviet weapons via the western side of the South China Sea began. The Vietnamese Politburo and the Central Committee's Military Commission made this decision in response to the arrival a few months earlier of several southern junks and their skippers pleading for weapons to fight. Communist leaders of COSVN authorised this overture to the north. Ngo Dinh Diem's effective crackdown on the remaining communist networks in southern Vietnam left them vulnerable to annihilation, if they could not fight back with modern and heavy arms capable of opposing those provided to the Republic of Vietnam by the U.S. Located far from 559's limited outlets into southern Trung Bo, southerners, especially those in MR 9 in Ca Mau and Tra Vinh, had no choice but to look to the South China Sea in order to obtain arms from the north.[86] Thailand was no longer a possibility; however, the man who ran arms to Nam Bo from Southeast Asia against the French, Duong Quang Dong (see above), organised this first, desperate southern maritime overture to the north. He had full COSVN approval.[87]

To do this, the DRV had to create a secret naval logistics unit. No longer could the ethnic Chinese networks be expected or trusted to run modern arms worth millions of U.S. dollars against vastly superior American naval power and surveillance. Moreover, the international context was such that the operation had to be an official DRV undertaking of absolute secrecy.[88] 759 received this mission, placed under the joint control of the Politburo and its Military Commission led by General Vo Nguyen Giap. 759's task was to create a functional and secret “strategic maritime route” running along the Vietnamese coast between Haiphong and the southern tip of Vietnam.[89] General Tran Van Tra, Deputy Head of the General Staff at the time, was in charge. The 759 group was outfitted with wooden- and steel-hulled vessels, the latter fabricated secretly in Hanoi and Haiphong or imported from socialist friends. Its crafts left from Do Son (secretly called K-20) near Haiphong, making their way through the Gulf of Tonkin, down the coast or hop-scotching across to Hainan and the small islands of the Paracels before darting towards the coast in search of inlets and reception points, linked to the interior of Vietnam by a myriad of rivers and canals. Waiting sampans or pack animals would quickly scurry the weapons to the inside of Vietnam and on to waiting troops and guerrillas. The landings usually occurred under the cover of night.[90] The majority of 759's captains and sailors were southerners, many of whom had been regrouped to North Vietnam after the Geneva Accords.[91]

The communist political and military leadership was surprised by the initial success of this southern inspired maritime operation. In October and November 1962, the 759's first four trips to Ca Mau delivered 111 tons of arms to zone 9.[92] From October 1962 to late 1963, a total of 23 missions delivered 1,318 tons of modern weapons and ammunition to southern Vietnam, mainly the provinces of Ca Mau, Ben Tre, Ba Ria, and Tra Vinh. From there, transport group Doan 962 and others distributed the war material internally.[93] In 1964, 49 vessels delivered 2,971 tons of arms and 113 cadres to southern Vietnam, while 408 tons of arms were delivered in the first two months of 1965.[94] These vessels could often make their trips in 8 days to the tip of Ca Mau, at relatively little cost and labour. Apparently, none of these early missions was detected much less intercepted. These weapons would outfit and arm the units fighting for Ap Bac against the Republic of Vietnam troops and their U.S. advisors.[95] When the first 759 vessel, appropriately named Phuong Dong I (Orient I), left Haiphong for Ca Mau in 1962, there to see it off were Pham Hung, Nguyen Chi Thanh and Tran Van Tra. Its skipper was a southern veteran, Bong Van Dia, who had run arms from Thailand to Nam Bo during the French war.[96] Phuong Dong II left shortly thereafter. Both of these Vietnamese junks followed the coastal maritime route, before successfully discharging weapon loads in the reception site of Vam Lung in Ca Mau in particular. The 759 vessels were in close radio contact, not only with their destination points, but also with the General Staff and even the head of the Central Committee's Military Commission, General Vo Nguyen Giap. This too was a significant shift in Vietnamese naval history. And it also pointed up the degree to which “guerrilla warfare” in Vietnamese hands was becoming a highly technical operation.

The South China Sea route seems to have had a much better success rate than the overland 559 operations. And it reached well beyond lower central Vietnam. Indeed, the success of these early supplying missions encouraged the Military Commission and the Politburo, lifting their faith in the effectiveness of the maritime route and its strategic value. While a debate occurred as to the diplomatic and military dangers this incurred in light of the Geneva agreements,[97] the south's military needs were simply too great: the southern communist networks were threatened with destruction and the overland Ho Chi Minh trail was nowhere near being able to supply Nam Bo via the inside in the early 1960s. In 1963, the DRV went a step further by creating a new operational office to run southern logistics, called “Section B” (Bo Phan B).[98] Under ultimate Politburo and Military Commission control, its functional operations were turned over to the General Staffs, the General Political Directorate, and the General Directorate of Rear Services. Section B worked directly now with 759.[99] The Vietnamese Central Committee decided to step up vessel production, and shift to making them out of steel so that they could better handle the rough weather and pounding waves of the South China Sea. Meanwhile, southerners developed additional receiving stations in lower central and southern Vietnam.

Given the international and national contexts at this conjuncture, the DRV leadership did not waste their time. By late 1963, the Central Committee' Military Commission had placed Group 759 and the maritime route under the direction of an emerging naval command (itself a response to these southern-inspired missions?). To mark the transition, in January 1964, Group 759 was officially renamed Brigade 125 by a decree of the Ministry of Defence. It became an official unit of the DRV's official Naval Command. This southern-inspired initiative had accelerated attempts already underway by the DRV to develop a real Navy.[100] Brigade 125 was equipped with 20 steel- and wooden-hulled vessels and its main mission was to deliver arms to Nam Bo, extreme southern Trung Bo and MR 5 below the DMZ. Emboldened by its successes, the DRV hoped to make larger vessels of 60 to 100 tons with steel hulls. In January 1964, the ship making industry in Haiphong produced five ships of 50 tons. And an unnamed “friendly nation” provided 15 more boats, each of which could carry between 100 and 200 tons of arms.[101]

This was not without results; the sea-borne route was operational. According to Vietnamese sources, between January 1964 and February 1965, Brigade 125 conducted successfully 88 missions to the south (including MR 5), delivering around 4,000 tons of arms. It also transported some troops and high-level political, military and technical cadres.[102] According to a recent Vietnamese military study,

until February 1965, we had used three wooden vessels and 17 steel-hulled vessels to make 88 voyages, transporting 5,000 tons of supplies, including many types of weapons, to the battlefield. Of all these voyages, only four encountered problems, when the vessels went aground or hit under water rocks, and in general all personnel and supplies arrived safely.[103]

On comparing different sources, I think it is more likely that this number of 4 to 5,000 tons refers to the total amount of arms and supplies transported between 1962 and early 1965.[104] What is certain, thanks to new Vietnamese studies, is that these arms definitely helped arm combat units in the south.[105] I would argue that the “Ho Chi Minh maritime trail” was probably more important than the overland ones up to and including 1965.

Other coastal areas below the 17^th parallel north of Nam Bo were soon interested in this new supply route. MR 5, in particular, asked Hanoi for arms via the sea borne trail. Vo Nguyen Giap felt that the South China Sea route should be reserved for Nam Bo, since it was the only route capable of reaching that far south. 559 overland operations, he felt, could funnel arms more easily to MR 5.[106] Nevertheless, the evolution of the war was such that speed was crucial and time was increasingly lacking. Giap eventually approved a supplying of MR 5. Reception points were opened at Vung Ro (Phu Yen), Lo Giao, and Sa Huynh to receive Brigade 125 shipments.[107] In June 1964, just before the Gulf of Tonkin incident, the DRV sent vessel 401 into Binh Dinh to try to help MR 5 outfit and arm its forces. In October 1964, the wooden junk 401 finally delivered its weapons at Lo Giao.[108] Vung Ro became a particularly important landing site for MR 5. Its relative deep-water port allowed for easier and faster discharging of 100-ton ships. Brigade 125 would send its first iron-hulled vessel (no. 41) to Vung Ro in November 1964, successfully delivering 44 tons of arms and munitions. It would make two more successful trips shortly thereafter. Thanks in part to these weapons deliveries (though only amounting to around 171 tons), MR 5 was able to increase its military activities in the winter and spring of 1964-65.[109]

Reinforcing the importance of the sea route at this conjuncture was, again, the difficulty 559 was encountering in opening a supply line west of the Annamese Cordillera via lower Laos. At stake was control of the strategic frontier zone between routes 8 and 12. The main objectives of the DRV's Campaign 128 between December 1963 and February 1964 was to control eastern parts of central and southern Laos, to support the Pathet Lao, and most importantly, in my view, to ensure that 559 could push a vital supply route from MR 4 to Nam Bo via lower Laos. The success of this battle provided 559 with 700 kms of a safe border with central and southern Laos, key for the 559's logistics operations west of the Annamese Cordillera.[110] The Central Committee's Military Commission was determined to push a route into Nam Bo via the western side of this range. In October 1964, as war with the U.S. seemed ever more likely, the Military Commission implemented “Plan S” (Ke Hoach S). From October 1964 to March 1965, 559 was instructed to transport 705 tons of arms and rice down the western side of the Truong Son.[111] While 559's results were still limited, this renewed attention to the overland operations in early 1964 came as the sea-borne supply line came under great pressure that same year. Strategically, all these routes were linked.

The Vung Ro Incident and its Impact

The largely unchecked maritime supplying of southern Vietnam from the north could not continue forever without drawing the attention of increasing U.S. surveillance and patrolling of the South China Sea. This became painfully clear on 15 February 1965, when Vessel no. 143 of Brigade 125 docked with 63 tons of arms at Vung Ro in MR 5.[112] After having begun to unload its cargo, it was detected by US air reconnaissance, attacked, and sunk in the bay. RVN troops finally took the area after fierce fire fights on the 19^th.[113] The 130 foot vessel was transporting 100 tons of Soviet- and Chinese-made weapons, ammunition, explosives and medical supplies. For Vice Admiral Paul Blackburn, commander of the U.S. Seventh Fleet, the Vung Ro incident confirmed that “sea infiltration into [the] RVN is now proved”.[114] A former member of 125 told American intelligence that the ships were delivering regularly 90 tons of arms, including AK-47s, ammunition, B40s and B41s, explosives and mines.[115] These increased supply missions came in the midst of the Gulf of Tonkin incidents of August 1964 and the accompanying Rolling Thunder and Barrel Roll air campaigns.[116] From this point, at war with both the U.S. and the RVN, the DRV had no choice but to step up its supply missions by land and sea to the south.

Increasingly committed to defending the RVN for a variety of strategic reasons, the U.S. would now double its efforts to block the DRV's logistics routes. For these reasons, 1965 clearly marked a turning point in the maritime nature of the war for Vietnam. The arrival of the U.S. 7^th fleet to the western part of the South China Sea after the Vung Ro incident made this clear to all involved, from the Politburo members straight down to the brave sailors running 125's missions across the sea and their counterparts charged with pushing the Ho Chi Minh overland trail further southwards. In March 1965, the 7^th fleet landed marines at Da Nang. The need to intercept sea infiltration became a top priority for the Americans and the 7^th Fleet became an integral part of the war for Vietnam, key to shutting down the DRV's use of the South China Sea from the 17^th parallel southwards. A naval blockade was instituted. It was coupled with bombing campaigns designed to interdict the overland Ho Chi Minh trail now moving steadily, but with great difficulty, towards southern Vietnam's western side via southern Laos and north eastern Cambodia. A very sophisticated and effective naval surveillance system was installed by the Americans to create a cordon sanitaire around all of southern Vietnam's maritime borders from the 17^th parallel to Rach Gia and Phu Quoc. The famous Operation “Market time” (Task Force 115) began in 1965 and lasted until 1970-71. This naval force conducted inshore and offshore patrols against DRV sea borne infiltration. Market Time worked in conjunction with “Game Warden”, in charge of monitoring the rivers, in order to deny all forms of water to enemy supply operations. The U.S. helped strengthen the RVN's navy by improving surveillance, increasing junk fleets, and introducing faster boats. The U.S. navy sent special missions north of the 17^th parallel to gather intelligence and to ensure a more effective blockade of the maritime route running eastward to the Paracel islands.[117] Operating from Subic Bay in the Philippines and various points in Vietnam, the U.S. introduced air surveillance of most of the South China Sea east and southeast of Vietnam. Added to this were Airborne Electronic Countermeasures (ECM), the use of PC-Orions, Neptunes, listening devices (decrypting), and, of course, radar. In short, the South China Sea was being covered in new and more modern ways than ever before in its history. Significantly, this had begun in a time of war and the DRV was as much a part of this mapping of the seas as the Americans who were trying to stop them. The French navy had only dreamed of such surveillance of the Vietnamese coast. For just southern Vietnam, the U.S. had 150 surveillance vessels at its disposal (among the most sophisticated of the time), whereas the French had only had 50 for all of Vietnam (few of which were cutting edge). American air surveillance of the western part of the South China Sea averaged 1,500 hours a month, whereas the French had never exceeded 500 hours.[118]

DRV strategists understood very well that the game had changed by 1965 following the Vung Ro incident.[119] As the U.S. stepped up its surveillance networks, Brigade 125 scored its last successes in getting through. Vessel 42, for example, delivered 60 tons of arms to Ca Mau successfully on 24 October 1965. Vessels 68 and 69 successfully followed, with similar quantities of arms.[120] However, U.S. intervention in Vietnam meant that the maritime route of Section B would be harder than ever to run at the very moment that Nam Bo would need modern and heavy weapons from China and the Soviet Union. The nascent DRV navy was about to enter into its most difficult period of the war for Vietnam.

1965-1970: Blocking the DRV from the South China Sea

Naval Brigade 125 now faced a serious American naval blockade of southern Vietnam from the 17^th parallel all the way to the Cambodian border. One important effect of this American blockade was that the DRV had to find new trails and new solutions in order to keep its sea borne route open to the south. New efforts were made to gather intelligence on enemy surveillance. Investigations into using international sea-lanes were launched. The DRV even opened special training courses on astronomical navigating for long-distance shipping far from the coast.[121] In October 1965, one of the first astronomical navigating vessels[122], no. 69, went wide into the South China Sea in an attempt to skirt U.S. destruction before running the blockade to the Vietnamese coast. The idea was to use the safety of international waters to avoid U.S. detection and/or destruction. However, getting lost in the middle of the sea was also a real fear. Modern navigational techniques and training were thus indispensable.[123] Knowing and using the islands and the Guangdong border of the South China Sea increased. Hainan became an increasingly important infiltration staging-point and refuge for failed missions.[124] The use of small islands in the Paracels, Poulo Condor, Phu Quoc, and other nearby islands were essential as stopover points ~~or as cartographic reference points~~.[125] Once locked on to identified islands, skippers could plot their coordinates and initiate their runs toward predetermined reception points on the Vietnamese coast. This was no easy task, for U.S. radar, air and naval surveillance, and decrypting were no technical pushovers.[126] In 1972, a DRV mission went wide into the South China Sea, hugging the waters of the Philippines and Malaysia before making a run for Ca Mau via the Gulf of Thailand. U.S. surveillance followed its every move. Its ships were waiting for it when it hit RVN waters off Phu Quoc.[127]

Indeed, U.S. surveillance picked up easily on vessel 69. The latter would escape attack by setting course in direction of Manila, with the option of heading towards Hong Kong. At one point, vessel 69 took refuge on a Chinese island. It was ultimately forced to return to northern Vietnam, marking one of the first in a long line of failed missions (noted at the time as “O” prob