Collective punishment is illegal under international law, but Israel doesn't take any notice when it doesn't suit itself.
As an example of IMO how barking American reaction is, some high American official said they will make sure that Israel has everything it needs to win against a few lightly armed fighters, that have been surprisingly quite effective against the Israelis initially.
It's like he doesn't know that Israel is one of the most militarised countries on the planet, armed with tanks, ground attack aircraft, and a very large army of thousands, but that guy is classing them as a "threat" to Israel. Considering that most of the military uses American weapons he must be a bit sad, IMO.