Viet Nam was no mistake other than not supporting Ho Chi Mein in the 40s once he went communist it was the right fight to make.You do realize that the Vietnam war was a tragic mistake, and that those who refused to go were right. The same demographic rushed to enlist in the aftermath of 9/11.
Not everyone who refuses to fight is a coward. I was once accosted by a guy in a bar who wanted to fight me. I told the bartender to call the police as "this guy was threatening to assault me". At that he backed off and left me alone. I didn't know him and he didn't know me.
However, while in the Army I was accosted by another soldier (for no good reason) and I had to fight him. Fortunately, I prevailed as I got the first punch in.