Nah, I don't think that ananlogy sums things up at all. There are alot of variables that aren't mentioned in your analogy. I'd think of it more like this. A cop has a history of busting a certain criminal. He's watched the criminal kill people and threaten people. The cop has visited this guy a number of times and asked him to give up his weapons and stop killing people. Each time the criminal tells him he dosn't have any weapons so get out of his house. The cop lets him slide, but is somewhat suspicious. The cop has even served the criminal with several warrants and had his house searched, but couldn't find any weapons. But for some reason, the criminal kept killing people. One day after the cop has heard about this criminal threatening more people, he comes to the guys house. This time, the criminal isn't so inviting and tells the cop to leave. The cop refuses to leave and, as he holds his weapon, tells the criminal to come out peacefully and give up his weapons. But the criminal keeps telling the cop to leave and that he dosn't have any weapons. So this time the cop yells at him to come out and give up his weapons. So the criminal steps outside almost challenging the cop. What's the cop supposed to do? He draws his weapon and aims it at the criminals head.

Now I think that is more accurate. What makes things more justified is the fact that Iraqi troops are killing our men and women. That would be like a bunch of this "criminals" buddies coming out of the house guns blazing.