Most of European citizens support Palestine yet European elites not so much.

Setting aside the priors of this comment, I don't think it's any great mystery as to why the US has tended to support the Israeli position.

https://en.wikipedia.org/wiki/Jewish_population_by_country#B...

The US has a higher Jewish-identifying population than any other country in the world, and Jewish people are more likely to be pro-Israeli policy, and they're more likely to influence their non-Jewish friends to be so.