I've been completely out of the loop on the whole drone strike issue, so I'm not going to try and provide any insight of my own.
I do, however, think that this official response to Rand Paul's filibuster by Atty. General Eric Holder is worth posting:
(if the image doesn't load for some reason, here's the text of Holder's response):
"It has come to my attention that you have now asked an additional question: 'Does the President have the authority to use a weaponized drone to kill an American not engaged in combat on American soil?' The answer to that question is no."