Hm. I see very well what the US does for Israel: 4.5 billion in military aid, constant international support (vetoed 44 UN security council resolutions against Israel), passed illegitimate laws in several states to punish those who support a boycott of Israel, recently recognized the illegal annexation of Jerusalem and the Golan Heights, puts orthodox Jews in charge of drafting peace plans with the Palestinians, etc.

But what does Israel do for the US? It's not very clear to me. The only thing I know of is intelligence. Is that enough? I think even Saudi Arabia provides much more support: military bases, etc.