Do you honestly think he would have voluntarily surrendered to the authorities to be extradited to the US?
Look, I appreciate your concern for the constitutionality of the operation, but I think you are missing something somewhere. I recall something about German terrorists who were US citizens actually living in the US during WWII, and my understanding is that SCOTUS agreed that they could be tried as enemy combatants in a military tribunal. If that’s allowed by the Constitution, then I suspect that flushing this piece of crud down the toilet is too.
No. I don't. And, like any other US citizen, armed and charged with a crime for which he has fled from US jurisdiction, his failure to surrender himself alone would be grounds to take him, and kill him if he resists. I also have no problem with killing him as a anonymous combatant in the company of other terrorists, and if the drone strike had not specifically targeted him I again would have found no fault. My issue here is that the President on his own and no other authority issued a kill order on a US citizen; he was not charged with a crime.
The Germans you're talking about were spies dropped off by a U-boat on the Florida coast, and sent to infiltrate the US as saboteurs. The SCOTUS ruled that military tribunals had jurisdiction. No surprise there. None of them were US citizens, and since they came to the US from a government with which the US was at war, they were handled properly. They had no presumptive right as "US Persons" under the Fourteenth Amendment, because they were not "subject to [US] jurisdiction."
They were not owed any Constitutional protections, and, as a matter of fact (just like al Qaeda) as non-uniformed combatants, they were not even entitled to the protections of the Geneva Convention.