Much has already been said of Mahmoud Abbas’s vilely ahistorical and anti-Semitic speech to the P.L.O.’s Central Council on Sunday. There is no need to go through a blow by blow of the Palestinian president’s repugnant claims that European Jews marched to the ovens in order to avoid emigrating to Palestine, his ludicrous charge that Israel has nothing to do with Judaism, or his nescient reading of history in which Zionist leaders conspired with Arab potentates to make their countries Judenrein in order to boost Israel’s Jewish population. Abbas’s screed deserves unqualified condemnation, and it only adds to his schizophrenic legacy.

Abbas has been a disappointing political partner for Israel, to say the least. This is not to say that Israel has made things easy for him, or that Israeli leaders have all been champing at the bit to strike a deal and have been stymied by an unwilling…