Aaron Copland in Hanoi

HANOI -- This year marks the 15th anniversary of diplomatic relations between the United States and Vietnam. The country is still a tender land, but the Vietnamese have long known how to profit from their various invaders over the past millennium.

American tourists, for instance, are now targets for hawkers of Viet Cong souvenirs around Hanoi’s Opera House. The theater is a scaled-down model of the Paris Opera’s Palais Garnier, and it was thus a glaring symbol of colonialism until the French were overthrown in 1954 and Ho Chi Minh made it a historic site for important political occasions, even if music and dance remain its main business.

On Friday night, though, the hall saw a different détente. American and Vietnamese musicians joined together to premiere new works by young composers from both countries and one by Elliott Carter, who is 101 and was born two years before the 600-seat Opera House was completed.

Aaron Copland’s “Appalachian Spring,” perhaps the most touching musical depiction of America as a tender land, closed the program and proved a moving culmination of two weeks of the Ascending Dragon Music Festival here, a cultural exchange between Southwest Chamber Music and the Vietnam National Academy of Music.