Generally I think he's been on the right side of history, but with the current situation I think he's let his personal ties with Israel through Judaism put him in a bad position.
I don't think it's uncommon amongst those in the Jewish community. They've been raised in families that saw Israel as reparations after the holocaust. To now acknowledge that "their own people" have turned into the oppressors that they escaped.... that's something many will be unable to accept.
I hear it's really splitting the British Jewish community.