As for the American soldier---yes, something may have snapped. But he will have to pay the consequences of his action. Unlike this killer, he turned himself in. And some day, it will eat at his conscience when he realizes what he has done not only to those poor families, but his own family.
Abbas to urge UN to pressure Israel to permit entrance to Palestinian refugees from Syria (Haaretz)
from the article: Live Coverage: French police surround suspect in Jewish school shooting