Remember, the target is not an American, they are an Enemy Combatant. Civilians that get in the way are not Americans, they are Collateral Damage. I want to believe that many of our service men and women wouldn't actually do that, but the Civil War makes me believe that to not be the case. They weren't Americans, they were the guys in Grey or Blue. Both sides proved that when it comes down to it you follow the orders of your leaders and fire at the guys in the wrong colored uniforms.
The soldiers from Vietnam, even Desert Storm are a different breed than what we have today for the most part. We still have a lot of great soldiers in uniform, but as far as command is concerned, I wouldn't trust any of them. There are too many gang bangers in the service today, too. It's a very sad and dangerous reality.
And with what we saw with Dorner and most recently in WA State, it's if they show up, all bets are off. Unless you want to be a crispy.
Remember Monkeys; Marksmanship is a perishable skill. Pratice if you got the ammo and if not, dry fire !