When former foes come together

In pursuit of the latter, Obama began decisively last year to pivot towards Asia in obvious counteraction against an assertive China. Vietnam fits neatly into that strategy as a counterweight.

This geostrategy explains much of the cooperative urgency: Commitment to early conclusion of the Trans-Pacific Partnership (TPP) trade agreement, and a “comprehensive partnership” to deepen security ties – a need that Vietnam also embraces, given its dispute with China over the Spratly Islands.

Mutual economic benefits will draw the two countries closer. The US has become the largest market for Vietnamese manufactures, which find little demand in China, even as cheap Chinese goods flood Vietnam, resulting in a deficit of US$16.4 billion last year. China imports mainly oil, rubber and coal from Vietnam, which fears it is becoming too dependent on China for such purchases and investments. In contrast, Vietnam had a trade surplus of $15.6 billion last year with the US.

Vietnam and the US, however, should realise the limits to their countervailing strategy. Hanoi can never be absolutely sure of the hand the US will play as the shape of geopolitics alters in step with changing circumstances in the region. For example, despite its countervailing value to China and the Soviet Union, it saw its war efforts imperilled when the two communist giants quarrelled.

War memories fade, but America is unlikely to lose interest in another of its eternal interests, however imperfectly pursued – human rights. Posing a real obstacle is Vietnam’s poor record – jailing political oppositionists, dissident bloggers and religious leaders – aggravated by endemic corruption. 

Obama was diplomatic in raising this point publicly during the visit: “All of us have to respect issues like freedom of expression, freedom of religion, freedom of assembly. And we had a very candid conversation about both the progress that Vietnam is making and the challenges that remain.” But deep concerns over mistreatment of workers and dissidents in Vietnam clearly occupy various American groups and cannot be ignored. A TPP agreement without any strong assurances on such non-trade issues might face difficulty winning congressional approval.