Originally Posted by ratbastid

I think it's probably from Vietnam. The way soldiers were treated when they came home from 'Nam was nothing short of disgraceful. The whole "support our troops" thing arose as a reaction to that.

The real tragedy, of course, is that as a nation, we learned the wrong lesson from Vietnam. And then that lesson got exploited for the pro-war agenda. Turns out that any criticism of the war now equals "dishonoring the troops". Which is ridiculous, of course, and an attempt to justify crushing free speech.