The Vietnam war was one battle in the larger Cold War. We lost that battle but won the Cold War without letting it turn into a nuclear holocaust. That was accomplished through both diplomacy and strategic use of military force, and something to be proud of as an American. Other countries helped us along the way, England being first on the list.
We should recall the nature of our enemy in the Cold War. Communist governments killed more of their own people in the last century than all the wars put together. This estimate puts it at around 150 million.
http://www.scottmanning.com/content/communist-body-count/
After we pulled out of Vietnam, the communists killed over 1,000,000 people there.
War is Hell, but communism is another level below that.
We fought to a draw in Korea and result created my favorite photograph of all time:
http://dssmithpc.com/satellite-images-of-north-korea-at-night-22.jpg
THAT is the difference between freedom and tyranny! Nothing more needs to said on the topic.
Stopping the spread of communism stopped the spread of oppression, starvation, and death. Europe hasn't had a massively bloody war since the US took over management of their defenses.
Most of the free people around the world owe some or all of their freedom to the blood and treasure of Americans. I am proud of that. No thanks are necessary, but sneering condescension will be challenged.