That is precisely false.
The Domino Theory proved true when communists slaughtered some two million people in Cambodia and Laos. They also killed tens of thousands of South Vietnamese, at least one hundred thousand died trying to escape, 1-2 million fled the country, and millions more were imprisoned in "re-education" camps.
The greatest human cost by far came after America abandoned its South Vietnamese allies.
You're exactly right. But in addition to the human cost, the whole SE Asia region has been lost economically to the world and to themselves since we left there. The lives given there in an attempt to help them gain freedom were very important. It is very unfortunate that we lacked the courage and leadership, especially in the media, to see that battle through.
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