Three decades after the United States and Vietnam established diplomatic ties, defense cooperation has emerged as a central pillar of their partnership. Focused on maritime security, capacity-building and operational engagement, the relationship has steadily deepened, reflecting growing strategic convergence.
Regional geopolitics and national priorities are driving the expansion, according to Nguyen Khac Giang, a research fellow at the ISEAS-Yusof Ishak Institute in Singapore. “First, China’s growing pressure in the South China Sea has made maritime security a daily problem for Vietnam,” Giang told FORUM. “Second, Vietnam wants to diversify, including its equipment base, its partners and its options, so it is less exposed to any single supplier or strategic shock in a growingly uncertain world.”
Hanoi and Washington have steadily bolstered defense ties, including with the transfer of a third U.S. Coast Guard high-endurance cutter to the Vietnam Coast Guard in mid-2025. The vessels enhance Vietnam’s maritime domain awareness and law enforcement missions in the nation’s internationally recognized exclusive economic zone, Giang said.
Maritime security cooperation was further strengthened by the U.S. Navy’s December 2025 port call in Da Nang, Vietnam. The visit of the amphibious assault ship USS Tripoli and the guided-missile cruiser USS Robert Smalls built on defense diplomacy dating to the USS Vandegrift’s landmark Ho Chi Minh City visit in 2003, the first by a U.S. Navy vessel since the Vietnam War ended nearly three decades earlier.
Initiatives such as cutter transfers and port visits seek to build capacity and confidence, Vietnamese academics wrote in the essay “Vietnam-United States Defense Cooperation In Addressing The South China Sea Issue (1995–2025),” published in January 2026 in an India-based journal.
Vietnam’s defense posture follows the “Four Nos” principle: no alliances, no alignment against other states, no foreign bases and no use or threat of force. Within this framework, Hanoi and Washington have boosted engagements.
In May 2025, Hanoi hosted the 13th bilateral Defense Policy Dialogue to align priorities and expand officer training. That same month, U.S. Secretary of War Pete Hegseth and Vietnamese Defense Minister Gen. Phan Van Giang met in Singapore, where they discussed broader cooperation in training and United Nations peacekeeping operations. Hegseth visited Hanoi in November 2025 to discuss collaboration in defense trade and information sharing.
The nations recently signed a memorandum of understanding to expand cooperation in post-conflict remediation, including unexploded ordnance clearance, while Vietnam’s Public Security Ministry agreed to purchase several U.S.-made helicopters.
The nations’ Comprehensive Strategic Partnership, signed in 2023, institutionalized military cooperation, Giang said. “The partnership gives both sides a wider policy envelope to do more — on maritime security, capacity-building, technology and training — without having to renegotiate the political meaning of every step.”
About the Author
