SINCE Saigon's fall to northern communist-led forces on April 30, 1975, Vietnam has put the war behind it and embraced free-market ways. Even though the war with the United States took a big toll, a reunified nation is now bounding with capitalist energy, Sony TVs, and American tourists. To the people, Vietnam is their country, not a war. Still, farmers feel left out and political freedoms are few. The US has withheld full ties until Vietnam does more to find soldiers missing-in-action (MIAs). But for Hanoi's leaders, the mantra today is doi moi (renovation) of the economy. And the Vietnamese are buying it.