If your argument is that the Vietnam War failed to achieve its goals, in context I don't see how sustaining the war for a millennium would have helped. The US a

If your argument is that the Vietnam War failed to achieve its goals, in context I don't see how sustaining the war for a millennium would have helped. The US arguably identified (correctly) that their approach wasn't working and stopped. They then crushed communism. I don't see an argument that communism is a credible ideology these days. We all know what will happen to any country that makes a serious go of it - the citizens will starve and the economy will collapse. Then they can't spread communist ideology any more because they're broke and humiliated. The defeat was so resounding that the options became liberal capitalism, authoritarian capitalism or irrelevance. If I hated someone enough that I wanted to bring war to their doorstep, and then decided that wasn't enough, I'd wish communism on them to. So insofar as the US was defeated in Vietnam, they won the war so much that the battle turned out not to need sustaining. I don't think this example shows any sort of survivorship bias, I think it is just a case where the project was achieved quickly.