“Legality” in this situation is completely irrelevant. The only law that would limit Kamala is the laws of politics. If she opposed intervention in Gaza, this would be the political equivalent of a frontal assault against a battleship. She’d be accused of helping Hamas, a bipartisan bill would be passed undoing whatever she does against Israel, and she’d be endlessly attacked by all sides in the media. If she opposed Israel annexing the West Bank, only the most extremist zionists would be against her on it for the reasons I stated.