If the US cut them off they would just turn to Russia. Putin and Netanyaho are like Putin and Trump. Russia would jump at the chance to broaden their foothold in the Middle East, and it would go perfectly with their narrative of fighting "Nazis" in Ukraine, and it would give the US a black eye.

The US should be doing far more to distance itself from what Israel is doing, but the only way it can actually stop it would be a committed invasion.