Many Asian countries welcome the U.S. pivot as a counterweight to China. While most are old American friends like Japan, South Korea and the Philippines, Vietnam is a striking new partner. Ties have steadily improved over the years. Today, the U.S. is Vietnam’s third biggest trading partner and its largest export market. High-level visits from the likes of then U.S. Secretary of Defense Leon Panetta and myriad defense memorandums have smoothed the way for stronger ties. In July the two governments inked the U.S.-Vietnam Comprehensive Partnership, aimed at boosting bilateral relations in several sectors, including “defense and security.”

“Washington sees Vietnam as the most strategic-thinking of all the ASEAN countries,” says Ernest Bower, Southeast Asia expert at the Center for Strategic and International Studies. “Vietnam has stepped up its game in amazing ways over the last five years. It’s incredible.”

The U.S. still has a 30-year-old arms embargo in place against Vietnam, but perhaps not for long. “It’s our assessment that U.S.-Vietnam ties have been steadily improving in recent years to the point that a lifting of the arms embargo is now conceivable,” says James Hardy, the Asia-Pacific editor at IHS Jane’s Defence Weekly.