Because they have Charlie Rangel as one of their spokesmen (sorry, no good URL):

The U.S. acted illegally when its soldiers attacked and killed Uday and Qusay Hussein, a leading Democratic congressman complained on Tuesday, before mocking the military maneuver that succeeded in eliminating the brutal duo.

“We have a law on the books that the United States should not be assassinating anybody,” Rep. Charlie Rangel, D-NY, told Fox News Channel’s “Hannity & Colmes.”

“We tried to assassinate Castro and we paid dearly for it,” the Rangel contended. “And when you personalize the war and you say you’re killing someone’s kids, then they, in turn, think they can kill somebody.”

When an incredulous Sean Hannity expressed dismay at Rangel’s comments, the Harlem Democrat shot back, “How can you get so much satisfaction that two bums have been killed? We got bums all over the world and some in the United States.”

Then Rangel mocked the U.S. military’s success in killing the two Hussein heirs, saying, “I personally don’t get any satisfaction that it takes 200,000 troops, 250,000 troops, to knock off two bums.”