When George W. Bush held Al Qaeda agents that were not American citizens in Gitmo, people had a fit about how the President was violating their constitutional rights.
When Barack Obama zaps an American citizen (Anwar al-Awlaki) without so much as a trial, no such objections are raised.
Logically, those who criticized Bush's actions but not Obama's must believe that killing people without trial is a worse violation than holding people alive (in a Caribbean island, no less!) and that people without American citizenship deserve higher protections than those that are American citizens.
Yes, I am glad the bastard is dead. No, I don't believe the President broke the law. But then, I don't think Bush did, either. My position is consistent: those who conduct war upon us have no protections in law. I would like to know how anyone on the Left squares their situation, though.