Mostly it's because the Marines are a part of the Navy that I feel so strongly about this topic. It is also due to the fact that the discipline exhibited by our forces, around the globe, has almost always been exemplary. You will not find US soldiers engaged in unseemly acts against resident populations. Why is that? The LA Times, not my favorite newspaper, has a nice OpEd piece about some of the culture of the Marines.
But it is more than that, even during the brutal years of our nation's genesis the armed forces of the United States exhibited a certain moral standard unmatched by other nations. During the battles with the Barbary pirates, the Marines earned the moniker "no worse enemy, no better friend".
Personally, I believe that the notion of our very founding (Life, Liberty, and the Pursuit of Happiness) speaks volumes to the behavior of United States citizens worldwide. It's not that our philosophy is the best in the world, but it is markedly better than the rest. Soldiers serving in Iraq, Afghanistan, Kosovo, the Horn of Africa, Haiti, Korea and other troubled spots around the globe have demonstrated what a well trained, professionally led military should be.
In my comments about the reprehensible Rep. Murtha, I labeled him a traitor for his broad generalizations of the actions of Marines involved in the Haditha incident. My assessment of this "public servant" remains. In time, the details of the events of that terrible day in November will become clear. Including reasons for any obscuring or concealing of facts from proper authority.
The Marines involved have my loyalty as a brother in arms, just as the families in Haditha have my sympathy for their losses.