The Vietnam War proved to be one of America's longest wars and one of the first wars in which America had failed to achieve any military objective. U.S. involvement in Vietnam grew tremendously in the 1960s as communism grew and as Eisenhower's Domino Theory about communism became widely adopted. It would ultimately be increased U.S. military aid, the Tonkin Gulf Resolution, and the rise of "hawks" that would gradually escalate the events of the Vietnam War.