Henry Nicholls / Reuters

It may have been at the Sternberg Center, where a large overflow marquee housed my London congregation on the High Holidays. There was an abandoned trailer in the woods behind it, and we kids would sneak out to play in it. I don’t even remember specifically when it happened. But I remember the sound of the word the first time I heard it spoken, its icy vituperation, the way the speaker’s jaw moved around the syllable. “Kike.”

Even so, until recently, “anti-Semitism” still struck me as a clinical concept, remote from my daily experiences. But Jeremy Corbyn has made it unavoidable. The leader of the Labour Party has managed to create a self-made political calamity of hypnotic proportions, one that could destroy his opposition party even as Brexit immolates the Conservative government.

From the beginning, Corbyn has flailed, unable to navigate the gray area of the anti-Semitism within the ranks of his own party. As a campaigner and backbencher, he long had the luxury of defining his career by what he rebelled against. Anti-war. Anti-nuke. Anti-Zionist. Now, though, people ask him more difficult questions. He still wants the benefit of the doubt, and gets testy when he doesn’t get it.

According to polling by The Jewish Chronicle, 85 percent of British Jews now think that Corbyn is anti-Semitic. And that was before this week’s bombshell: documents obtained by The Sunday Times showing that Labour failed to investigate hundreds of anti-Semitism complaints, and let hundreds more slide. The documents show not only that Labour’s procedures for investigating anti-Semitic incidents were—despite public assurances to the contrary—dismally subpar, but also that members of Corbyn’s office directly intervened in more than one in 10 investigations, despite having claimed that they were impartial.

A council candidate who said that Jewish members of Parliament were “Zionist infiltrators” was allowed to continue his campaign. Out of 863 alleged incidents detailed in the files, only 29 resulted in a party member being expelled; 145 resulted in a “formal warning”—which is largely meaningless—and 191 cases were resolved as requiring no action. The rest, the Times reports, are unresolved, including 249 that haven’t even been opened.

A Labour spokesperson said that the report “does not reflect the full details … and is not up to date,” a non-denial that did nothing to stem the bleeding. That evening, the Jewish Labour Movement—one of the party’s oldest affiliates, linked to Labour since 1903—passed a vote of no confidence in Corbyn.

A year earlier, in March 2018, the story broke that Corbyn had been a member of three secret Facebook groups in which virulent anti-Semitic memes were sometimes shared. Understandable, perhaps, in radical campaign circles. My enemy’s enemy is my friend, right? We’re protesting an occupation, not forming a government. There’s nothing anti-Semitic about deploring Israel Defense Forces violence in Gaza, but if Palestine is your cause, sometimes you’re going to meet people who really just hate Jews—just like if Israel is your cause, sometimes you’re going to meet people who really just hate Muslims.

In one of the groups, Corbyn wrote supportively to the artist of a mural in London. It wouldn’t have been so bad—just a throwaway comment—except the mural depicted anti-Semitic tropes so blatant you could see them from space, hook noses and all. Corbyn trying to apologize was an agonizing sight. “I sincerely regret that I did not look more closely at the image I was commenting on,” he said. “I am sincerely sorry for the pain which has been caused.” It was as if, in a lifetime of fighting for causes—framing the world as good versus evil—he never really learned how to say sorry.

Corbyn’s unlikely leadership bid activated a die-hard grassroots base, which coalesced when he won into an organization called Momentum. It also brought floods of new members into the party. In December 2014, the year before he ran, Labour had 190,000 members. In two years, that almost tripled. Some were hard-left-wingers, returning after Tony Blair–era exile. Others saw in Corbyn an antidote to politics as usual, a political messiah in tweed. Had they been American instead of British, they might have backed Bernie Sanders in the primary, then Donald Trump in the general.

Until the general-election upset in June 2017, when Labour stunned pollsters by increasing its vote share, Corbyn seemed unlikely to stick around for long. But that victory—of sorts—trapped him. After the election, MPs who thought they could wait him out grew restless. Luciana Berger, a Jewish Labour MP, had been perennially targeted for abuse, both anti-Semitic and misogynistic, mainly from the far right. But when she started talking about anti-Semitism in Labour, when she expressed concern about Corbyn and the mural, something changed. Some of the abuse seemed to be coming from Labour supporters, even members. “One person told me: ‘Momentum will be watching you,’” she wrote.

The dismal carousel kept spinning: revelation, denial, proof, non-apology, repeat. Under pressure, Corbyn got more and more defensive. In August, when video of him talking about some Zionists who “lived in this country … all their lives” but “don’t understand English irony” sparked fresh outrage, his response was downright sulky: “I am now more careful with how I might use the term Zionist, because a once self-identifying political term has been increasingly hijacked by anti-Semites as code for Jews.”

Because of the threats against her, Berger needed a police escort to attend the Labour Party’s annual conference in September. Damningly, just six weeks later it emerged that Labour had known about a specific threat against her by a party member—and had covered it up for six months, telling neither her nor the police until an internal dossier of threatening posts by Labour members got leaked to the press.

Two party members in her constituency—one of whom posted comments online calling Berger a “disruptive Zionist”—filed no-confidence motions against her for “continually criticising our leader.” The votes were withdrawn, but it was the final straw for Berger, who quit along with seven other MPs, saying that she could not remain “in a party that I have come to the sickening conclusion is institutionally anti-Semitic.”

The longer it plays out, the clearer it is that Corbyn’s struggle with anti-Semitism lies not just in his unwillingness to confront it, but in his inability to acknowledge it as a problem—or even feign interest. The week Berger left, video surfaced of Chris Williamson, a minister in Corbyn’s shadow cabinet, at a Momentum event. He said that Labour had been “too apologetic” about anti-Semitism. Only after a near-revolt among Labour MPs, including the deputy leader Tom Watson, was he eventually, reluctantly, suspended.

With Corbyn’s leadership assured by tens of thousands of new members who swept into the party and delivered it to him, he should now be free to remake it in his own image. Labour should be the Corbyn party now. In some ways it is, but—paradoxically—the reverse is also true. Momentum might be more aptly named than anyone had suspected. Distracted by the anti-Semitism scandal, instead of leading his party, Corbyn seems more like the driver of a runaway train, barely holding on as it barrels onward.

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