>>214169675
The strategies in Vietnam/Korea were simple: dump troops/bombs/money into specific chokepoints, exhaust the other side hoping to contain their momentum elsewhere. They even drew the same no-go middle lines and refused to engage in any serious offensives past those. Ultimately they didn't really want to provoke China, which they knew is what would happen if they pursued the wars all the way through to their border. It was basically their compromise. S. Korea managed to put together a functional state to hold down the fort after we left and S. Vietnam did not, that's the only difference. I'm not going to bother arguing that Vietnam wasn't a loss because most people only understand warfare on a simplistic level but the intention was never to "conquer" all of Vietnam, simply to dig in and slow down the progress of communists, which was VERY rapid at the time.
And what do you know, China liberalized after and the USSR fell 15 years later, so something must have gone right.