Having him in the sights at that point in time.
When you got the deer in the sights you pull the trigger. You don’t call your wife and say, “Dear I have this awesome deer in my sights right now!”
You would have tags for that deer or you would be a poacher. Your argument is a non sequitur. Deer aren't American citizens.
We already knew Al Awlaki was a problem long before we located him. There was plenty of time to obtain a warrant. If you haven't got anything better than that, you don't have anything.