Monkeys and organ-grinders
Not ALL the blame, I would suggest: the various Israeli regimes over the decades since it came into being have proved themselves inventive innovators in vileness. But it is undeniable that they have felt able to do so because of the knowledge that no abrogation of international law, no human rights abuse, no persecution of minorities, no stamp of the jackboot on political freedom would ever be punished, because the United States would always be on hand to offer justification and support. And of course to provide the bottomless pit of money, without which Israel's economy would tank in a matter of months.
The only American president with the balls to stand up to Israel and threaten to turn off the money spigot if it proceeded with yet another plan to launch a sneak attack on a neighbour (in this case Egypt) was Eisenhower. Plenty of others have talked the talk, but at the end of the day Israel was always allowed to get away with murder. Hundreds of thousands of murders, in fact.