Can Kamala, or even Joe Biden, just flat out stop supplying them with weapons until there is a ceasefire?
Well let's walk through what happens.
We announce no more weapons for Israel. Israel is attacked by Hamas or Hezbollah a short time later. The blame for weakening Israel falls to Biden/Harris for their lack of support. A large enough number of Israel supporters drop their support for her, and she loses the election.
Trump wins, weapons flow back, Bibi allowed to do whatever he wants.