During the Vietnam War, President Lyndon Johnson and the military argued that we had to win in order to prevent communism from taking over other nations in the vicinity, the so-called domino theory. The military asserted repeatedly that provided we sent over more troops, they could win the war. They also argued that we needed to get the local people on our side, which, not surprisingly, we were never able to do. Government officials argued that we could not leave Southeast Asia because that would be admitting defeat; the families that had lost loved ones would feel their sons and daughters had died in vain.
Unfortunately, over 58,000 did die in vain. Another 150,000 plus Americans were wounded. Those figures ignore the million-plus North Vietnamese who lost their lives and the quarter of a million South Vietnamese who were killed.