What do you not understand about war?
There are no courts, warrants, etc.
The burden of proof for getting on the "kill list" is a lot lower than a court of law "by design". Could you imagine the total cluster F that would be caused if we had to show all the top secret sources of info as to all the detailed info we have. This would be in addition to the self-incriminating videos they keep putting out.
Like I said before, guilt by association (with Al-Q) is a real bitch in wartime.
For those of you who have not seen it, here is Al-Aulaqi in a video with Al-Q. Doing that, he basicaly signed his own death warrant.
http://news.bbc.co.uk/2/hi/8645972.stm
Anyway you slice it, he brought this upon himself.