What do you mean "you people?" I didn't send them into war. Besides, they weren't shot as punishment. They were killed fighting in a war that our government thought we needed to help the underdogs with against an oppressive Government. The 58,000+ that were killed fought believing that they were helping a small country overcome a communist dictatorship and to remain free. That didn't work out and with China and Russia aiding the oppressors, there was probably no way we were going to win that war without complete devastation of both countries (N. & S. Vietnam), which would have resulted in the loss of; God only knows how many lives.
Someone once asked why the U.S. just didn't fight that war from the air and it would have been over quickly. Maybe yes, maybe no, but when you drop bombs, you can't choose who is going to die and who isn't. Even so, when fighting with ground troops, there is still going to be collateral damage with loss of life to civilians. Dropping a nuclear bomb would have had long-lasting affects for the U.S., both politically and economically.
The U.S. probably shouldn't have ever gotten involved in it from the start, but we were just trying to do the right thing. Our government had the auspicious idea that once the North saw our might, they would cave and leave the South alone, but we were wrong. With allies like China and Russia wanting to kick our ass for years, it was only practical for them to jump in and help their neighbor and friend.