After 1 1/2 years in RVN and 9 years total service I began to educate myself. That is, I read history. Not the Vietnam War accounts of individual firefights or novelized history, but true history treatises.
Initially I was convinced that the US was saving SE Asia from communism and the "Domino Effect," so I was determined to participate in that effort. Later, as my knowledge increased, the revelation that our involvement could have been avoided by simply not supporting a colonialist France (a bit ironic) and supporting North Vietnam in seeking independence. Ho Chi Minh's declaration of independence was nearly word for word America's declaration. In 1946 we were on the ground floor in introducing democracy and then blew it by supporting France. The next tragedy of Vietnam resulting in countless dead was Lyndon Johnson's management of the Tonkin Gulf lie.
Fast forward to Iraq and the dubiously supported weapons of mass destruction theory. No ground truthing or other tangible support of weapons of mass destruction could be found in Iraq. Powell, Tenet, Rice, and others argued against invading Iraq but could not alter Cheney's and Rumsfeld's momentum for war.
Afghanistan is a country that has never been successfully invaded, reconstructed, conquered, etc from the time of the Persian kings to the present. It is a mess that is a historical quicksand pit for foreigners. As we wonder why democracy is not gaining in Afghanistan we must realize a simple fact: they do not think the way our politicians think.
Back to Vietnam era hippies - mostly frightened young men that had no desire to be drafted but also a few that knew the history behind the Vietnamese conflict.