When captured, Eisenhower immediaely ordered them shot as spies, and this was done, without apology and no legal case was made as done here.

Is there any difference in a targeted execution other than these American combatants are not firstly captured, interviewed and then shot?

Let us not forget that a smoking gun is not necessary to prove capital guilt, certain Japanese Generals were hanged for losing control over their responsibilities towards Philipino civilians as the war drew to a close and their army ran amok.

Awlaki was a combatant civilian, not covered by the Geneva Convention concerning wars, serving behind the lines, but not out of harm’s way, he is simply a casualty of war, nothing more or less. He was vocally proud to be an active ‘terriorist’ and willing to take the risk of personal harm.

Fortunatley, the assasin was assasinated first.