It's definitely ironic, that Jews, in an effort to defend against anti-semititism, are, by supporting the Left, inadvertently helping to set up the very conditions that foster and nurture it.
But the anti-Semitic Left is still small in this country, as opposed to Europe. And the Blacks arent really feared because of their relative powerlessness (historically). Of course, once they find they can't truly influence the Democrap agenda, they might bail. And Israel is the key starting point, IMO.