I will support him. I may not agree with his politics but America for too long has been controlled by Israeli influence. Next I would like to see AIPAC designated as a foreign agency and functionally dismantled, any politicians who were beholden to AIPAC should be gone. A national democracy should never have a single entity like AIPAC.
Is it unlikely? Is he possibly just stirring up controversy? Maybe, but even if that's the case no American president before him had dared threaten Israel since the 60s.