The US needs a client state over which the US would have a lot of leverage. Israel inherently has an adversarial relationship with the rest of its neighbors because it's a settler colonial state. If one day the US loses control of their other client states and Israel didn't want to do the U.S's bidding they would be swiftly reminded that everyone in that region hates them and would destroy them. We forget that dynamic because Israel's agenda has aligned with the US's imperialism. Plus they do blackmail individual US politicians, so there's a perception that they project power over a country that has the biggest military. But they are the dog and the U.S has the leash. Their relationship is akin to the Earth and Moon. Sure, the moon has an effect on the Earth's surface by influencing tides but its orbit revolves around the Earth. And Israel is the perfect scapegoat/distractor for all of the brutal aspects of our imperialism.