We were trying to stop communism in Vietnam. That failed.
Of course, the real problem was fear of communism. I don’t particularly want to live in a communist country, but a great many Vietnamese people did. What right do we have to stop them from choosing communism for their country? That is the real failure in Vietnam.
In the 1950s, there was an irrational fear of communism running through parts of the US. That fear worked its way all through the government, including Congress and parts of several administrations. Presidents from Eisenhower through Nixon got caught up in this irrational fear, with ever increasing commitments to the war in Vietnam to appease the Red Scare folks.
Hopefully staying on the right side of the political line here, it’s worth pointing out that history rhymes. We’ve got irrational fears running through the population - and therefore, government - again, leading to less than ideal decision making.
But getting back to topic, the war in Ukraine is of a different nature. We are not trying to influence politics internal to a country, we are supporting one country who was invaded by another. In general, that has a much better chance of getting broad support and having an easily measurable and very achievable goal.
–Peter