The line he’s walking right now definitely isn’t working but saying that cutting support to Israel and sanctioning them “would pretty much guarantee” him the election just is not true at all (unfortunately). It’s not even close to true.
Biden could pretty much guarantee a win tomorrow by announcing that it has been determined that Israel is indeed committing war crimes, followed by cutting support for them as per the Law when the recipient of help is committing such crimes, ideally followed by sanctions.
I wish this was true but it very much isn’t. He’d immediately lose Pennsylvania, at a minimum.
Traditionally it meant Soviet apologists. Now it gets used more generally for the authoritarian left, where the horseshoe starts curving around.
I definitely do not think it does, and I agree with the rest of your post that neutrality would be a better path forward