That same finger can be pointed right back at those same people who sing the praises of the CCP. Eventhough the CCP and not America wrecked the entire world economy with the Coof release. There is an old saying "Whenever you point a finger at somebody 4 are pointing back as you.
Yes, that is absolutely true; Vietnam helped enable the rise of the Far-Left and the people who sold us out to the CCP.
Because Vietnam destroyed the myth America had built for ourselves about the righteousness, and ability to win any conflict, and the 'goodness' of the US gov. I know militarily, we did decently well, but the political battels were lost, so combat gains, and sacrifices, effectively meant nothing in the geopolitical conclusion of the conflict.
A lot of Americans realized that mythos only existed to mostly pat ourselves on the back about WW1 and WW2 in perpetuity, and enable the excesses and abuses of the military-industrial complex for decades.
Vietnam was when the dream and mythology of a 'righteous' America ended for many Americans and most of the world; we've just had a lot of people who do not want to admit that, because of what it means for all the sacrifices of our troops, and their own PR. This shit in A-stan is just confirming what a lot of the world already knew; the US is not a dependable ally or even protector of our own people.
Unlike a lot of the people on the Right, I never saw America as a 'shining city on a hill', I was never raised in that mythology, and I think that mythology is...more about national pride than about somber analysis of the US as just another country. We are an exceptional nation, but not as much as our mythos would like us to think.
We have been culturally a lot close to the oligarchy of Russia and the CCP for a while, our elites just hid it better, and now that the corruption is out in the open...well, it's causing some people to question if the US even
deserves to win anymore.
Edit: Reminder Watergate happened in this time period as well, had a huge rule in damaging public trust in the US gov.