During the question-and-answer session following his speech at the Shangri-La Dialogue 2026, To Lam, Vietnamese President and Secretary General of the Communist Party of Vietnam (CPV), pledged that, despite its growing visibility, Vietnam would not seek to become a “power center” in Southeast Asia. Observers of Vietnam’s foreign policy cannot help but compare this engagement with Vietnam’s attempt to lead an Indochina bloc composed of Laos and Cambodia, confronting the Association of Southeast Asian Nations (ASEAN) during the Cold War.
Instead of siding with a great power and weakening ASEAN, Vietnam now asserts its Four Nos foreign policy (no military alliances, no siding with one country against another, not allowing foreign powers to establish military bases in Vietnam or use Vietnamese territory against another, no use or threat of force in international relations) and advocates “ASEAN centrality.”
Lam’s commitment is even more remarkable in the context of China’s growing presence in Laos and Cambodia. Modern Vietnam has considered its two western neighbors as part of its sphere of influence since 1945 and is concerned about the possibility of a Chinese-dominated Laos and Cambodia. However, Vietnam renounced the use of force to keep Laos and Cambodia in its orbit under the Four Nos. Lam’s rejection of Vietnam’s role as a “center of power” appears to reinforce this notion. However, it is not because Vietnam does not intend to become a center of power that it will abandon Laos and Cambodia to other powers. The strategy now consists of maintaining its influence in Laos and Cambodia without being perceived as a regional hegemon.
Vietnam’s final objective towards its two western neighbors is consistent: to prevent any hostile great power from establishing a presence there. Laos and Cambodia alone cannot pose a military threat to Vietnam due to their smaller populations and economies. Vietnam’s population of 103 million is about four times the combined population of Laos and Cambodia. Nevertheless, they can serve as a starting point for the great powers to attack Vietnam from the west. Vietnam shares a 3,400-kilometer-long border with Laos and Cambodia, and lacks horizontal strategic depth. Such geographic weakness would force Hanoi to constantly station several hundred thousand troops along the border if it is unsure of Laotian and Cambodian intentions. As such, nurturing friendly governments in Vientiane and Phnom Penh is essential if Vietnam is to maintain calm on the “Western Front.”
Vietnam’s strategy towards Laos and Cambodia throughout the three Indochina wars reflects Hanoi’s determination to keep its western neighbors in a zone free of foreign influence by manipulating the leaders of the two small Indochinese countries. During the First Indochina War (1946-1954), the Democratic Republic of Vietnam (DRV) waged a war of independence against France not only on Vietnamese territory but also throughout the rest of Indochina.
This was due to geographical necessity. Hanoi feared that the French-backed regimes in Laos and Cambodia would continue to pose a threat to its fledgling communist government. The DRV created communist sister states in Laos and Cambodia to fight against the royalist governments of those countries. The western flank was so important that the Vietnamese communist leaders decided to concentrate their forces on Dien Bien Phu instead of the Red River Delta. This involved opening a Vietnam-Laos-Cambodia front to force France to spread its forces throughout Indochina – exactly the disadvantage the French wanted to avoid.
With Chinese support, the DRV successfully neutralized Laos and Cambodia from French control under the Geneva Accords of 1954, with France expected to withdraw from Indochina. However, he failed to gain international recognition for the Cambodian communists and achieved only limited recognition for the Pathet Lao. This is where Hanoi’s geographical pragmatism took precedence over its ideological commitment to its Laotian and Cambodian comrades. After Geneva, the DRV was prepared to coexist peacefully with the royalist governments of Laos and Cambodia and prevented Laotian and Cambodian communists from leading revolutions as long as the royalist governments respected the Geneva Accords by not joining military alliances. This was also the general line of the international communist movement at the time.
This tolerance quickly expired at the start of the Second Indochina War (1955-1975). This time, the DRV perceived that the United States sought to undermine the neutrality of Laos and Cambodia by sponsoring pro-American groups within their respective governments and placing them under the protection of the Southeast Asian Treaty Organization. In May 1959, right-wing elements excluded the Pathet Lao from the neutral Royal Lao Government (RLG). This prompted Hanoi to increase its military support for the Pathet Lao to resist the RLG. The Geneva Conference on Laos in 1962 did not change Hanoi’s course. As the war against the US-backed Saigon government intensified, the DRV needed a friendly Laotian government to protect the Ho Chi Minh Trail and suppress cross-border commando insertions into its territory, and the RLG could not meet this demand.
The same goes for Prince Norodom Sihanouk’s Cambodia. Hanoi was willing to tolerate his government and its limited support for Cambodian communists as long as Sihanouk let DRV troops establish camps and use Cambodian territory to launch attacks against American-backed South Vietnam. However, after the overthrow of Sihanouk by the pro-American general Lon Nol in March 1970, Hanoi stepped up its military support for the Cambodian communists who were waging war against Lon Nol. With support from China and the Soviet Union, the DRV succeeded in forcing the United States to withdraw from Indochina in January 1973, bringing the Laotian and Cambodian communists to power in 1975. Hanoi believed its western flank was finally stabilized.
The Third Indochina War (1978-1991) showed once again how determined Vietnam was to keep its western flank free of foreign powers by maintaining friendly governments in Cambodia and Laos. Soon after seizing power in Cambodia in April 1975, the Khmer Rouge became a new threat to the unified front in southwest Vietnam. Vietnam tried to negotiate territorial disputes with it, but all attempts failed.
However, what worried Vietnam was not the military power of the Khmer Rouge but their Chinese support. Vietnam could have overthrown the Khmer Rouge in late 1977, but it then decided to launch only limited counteroffensives, so as not to antagonize China. However, the presence of Chinese military advisors in Cambodia and their role in arming and planning attacks against Vietnam after serious Vietnam-China talks in October 1977 worried Hanoi. With Soviet military support, Hanoi decided to overthrow the Khmer Rouge and replace them with a pro-Vietnamese government in 1978 in order to neutralize Chinese influence in Cambodia. The fact that Vietnam was able to install a new Cambodian government just two weeks after launching the invasion in December 1978 showed the power disparity between the two neighbors.
As for Laos, Hanoi won Vientiane’s allegiance by promising to protect it from Thailand and domestic rebels. In exchange, Vientiane downgraded its diplomatic relations with China and limited the presence of Chinese engineering troops there. The 1977 Vietnam-Laos Treaty of Amity and Cooperation allowed Hanoi to station troops on Laotian soil to guard Vietnam’s western flank as well as to put pressure on Khmer Rouge remnants along the Laos-Cambodian border. In January 1979, Hanoi had two friendly governments on its western flank.
However, such use of force has proven costly. Vietnam stationed 50,000 troops in Laos and 200,000 troops in Cambodia to protect pro-Vietnamese governments there. At the same time, it had to prepare for the possibility of a second Chinese invasion after February 1979 on the border between Vietnam and China. Internationally, Vietnam has been condemned by the West, ASEAN and China as a regional hegemon and subjected to heavy economic sanctions. Due to the decline of the Soviet Union, Hanoi had to abandon the use of force as the primary method of keeping Laos and Cambodia free from great power interference. It withdrew from Laos and Cambodia in 1988 and 1989 respectively and accepted a non-aligned Cambodian government under the 1991 Paris Peace Accords.
After 1991, Vietnam adjusted its strategy towards Laos and Cambodia. Instead of relying on military might and a great power ally, Hanoi emphasized political arrangements aimed at strengthening the non-aligned status of Laos and Cambodia. The 1977 Treaty of Amity with Laos remains the foundation of Vietnam’s efforts to keep Laos safe from foreign powers, as the treaty commits both sides not to undertake actions that harm each other’s interests. Laos receives Chinese funding for its infrastructure, but it does not host Chinese military bases.
With Cambodia, Hanoi has strictly adhered to the 1991 agreements prohibiting the sending of troops to Cambodia, which is also in line with its Four Nos. Above all, this decision allowed Hanoi to bind others to the same commitment, since the Paris Peace Accords committed all signatories, including France, the United States and China, not to station troops on Cambodian soil. The Cambodian Constitution of 1993 explicitly prohibits the establishment of foreign bases on its soil. This is what Hanoi wants. Vietnam also supports the Hun family’s domestic rule, even as Cambodia moves closer to China under Hun Sen’s leadership.
Indeed, the Hun family is less likely to seek foreign aid to counter Vietnam than other more anti-Vietnamese Cambodian factions. China’s growing presence at the Ream naval base certainly raises concerns in Hanoi, but it is a far cry from China’s support for the Khmer Rouge in their attacks on Vietnam. Vietnam, for now, is countering Chinese influence in western Indochina by waging its own infrastructure war and building vital ports and waterways linking it to Laos and Cambodia.
Vietnam is likely to continue integrating its Laos and Cambodia strategy into ASEAN via an expansion of the Four Nos. “ASEAN centrality” keeps the region, and particularly western Indochina, free from major power interference without Vietnam being seen as imposing its will on others. Until China and other major powers turn Laos and Cambodia against Vietnam, Vietnam is unlikely to resort to the use of force to manipulate the leaders of Laos and Cambodia as it did in the three Indochina wars.