The War in Vietnam Direct U.S. military participation in The Vietnam War, the nation's longest, cost fifty-eight thousand American lives. Only the Civil War and the two world wars were deadlier for Americans. During the decade of Vietnam beginning in 1964, the U.S Treasury spent over $140 billion on the war, enough money to fund urban renewal projects in every major American city. Despite these enormous costs and their accompanying public and private trauma for the American people, the United States failed, for the first time in its history, to achieve its stated war aims. The goal was to