That’s why Bibi’s recent behavior has been such a disaster. After agreeing in 2009 to support some sort of Palestinian state, he declared in the final days of his reelection campaign that he did not. This puts AIPAC, which on its website declares its support for “a negotiated two-state solution—a Jewish state of Israel and a demilitarized Palestinian state,” in a bind. If AIPAC abandons its support for the two-state solution to stay in line with Bibi, it risks alienating some of its secular, Democratic (and democratic) members, who might drift toward the dovish pro-Israel group, J Street. But if AIPAC allows any public distance between itself and Bibi, it risks alienating its more hawkish members, who generally oppose any American criticism of an Israeli leader, especially Netanyahu, whom they particularly admire.

More broadly, Netanyahu in recent months has become a deeply polarizing figure in the United States. Republicans love him not only because he’s a hawk but because he’s an Obama foe. Many Democrats loathe him for the same reason. For Jewish groups with strong partisan identities, that’s fine. Democratic-leaning J Street galvanizes its members by defending Obama against Bibi. Groups like the Zionist Organization of America and Rabbi Shmuley Boteach’s This World: The Values Network—which enjoy funding from right-wing billionaire Sheldon Adelson—galvanize supporters by defending Bibi against Obama. AIPAC, caught in between, says nothing and looks irrelevant.

AIPAC’s far from irrelevant. It remains the most powerful American Jewish group in Washington. But it is not built for this highly partisan, highly ideological age. Among ordinary voters, a chasm is opening up between the way Republicans and Democrats see Israel. Republicans see it as an outpost of Judeo-Christianity surrounded by America-hating Muslims. Democrats see it as a country led by the very “neoconservatives” they can’t stand here at home. AIPAC needs to keep that chasm from splitting Washington. It needs Democratic members of Congress to resist the instincts of their voters. And it needs Republicans to avoid pandering to their voters by exploiting Israel for partisan gain, and thus alienating Democrats even more.

Isaac Herzog would have been a good partner in that effort. His respect for President Obama would have reassured Democrats. But his status as an elected leader of the Jewish state would have won him the deference of most Republicans. Most likely, he would have supported the two-state solution without prioritizing it, thus allowing AIPAC to say what it always has: that the absence of a Palestinian state is the Palestinians’ fault. Several more years of Bibi, on the other hand, will make Israel an even more polarizing issue in the United States. Which means that, for AIPAC, Tuesday was a very bad day.

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