According to the latest news, America’s curmudgeonly old socialist, Bernie Sanders, is officially back in the running for President of the United States—a development which has caused no end of joy for followers of Britain’s Jeremy Corbyn, leader of the Labour Party, and a man many on the British left see as his kindred spirit. Each of them has come from nowhere to radically reshape the left of his country’s political spectrum. “That’s the special relationship I want to see,” tweeted one frontbencher and close ally this week. The tragedy is that, just as America’s socialist’s star is rising, his UK counterpart’s looks to be in terminal decline. This week, seven Labour MPs left to sit in an independent grouping, with three Conservatives joining days later. More are expected to defect in the coming weeks and months.

With reports of another election once again appearing in the British press, and Corbyn still favorite to be the next prime minister, we might assume that a chance to put his prospectus to the country again would be welcomed. Things have never looked darker for the Labour leader, however. A belligerent attitude towards Britain’s Remain voters in 2016’s Brexit referendum, a continuing affection for authoritarian regimes, the rolling crisis of anti-Semitism and this week’s defection of seven Labour MPs from the party have formed a vortex from which many feel he may never be able to extricate himself.

After a year of controversy, polls released in February show that just 17% of voters are satisfied with Jeremy Corbyn’s performance, a record low. A YouGov poll conducted at the beginning of the month had him in third place behind May, who had the support of 40%, and Don’t Know, which took 39%. Only 19% of voters believed Corbyn would make the best Prime Minister. After an eventful four years at the helm, fighting for a job—Prime Minister of the United Kingdom—nobody ever expected for him, least of all himself, is Britain’s radical socialist taking a stumble?

Corbyn was first elected to parliament in 1983 at the age of thirty-three, just as blood-red socialist politics in Britain was entering a period of long decline. That year was Margaret Thatcher’s second election win, and Michael Foot, the Labour leader she beat in a landslide, was the party’s most left-wing in a generation. It was the closest Corbyn’s style of politics would come to the top of the Labour party for over thirty years. Until his sudden and miraculous elevation to the leadership in 2015, he and his Socialist Campaign Group (the small caucus of MPs with which he shares his style of politics) were the most isolated in the party. During Tony Blair’s New Labour years, he rebelled on votes a total of 428 times, often making him the most rebellious Labour MP of the year.

Times did change, as we know. After Labour’s defeat in 2015, Corbyn was picked to be the candidate of his caucus in the upcoming leadership election—a fruitless tradition they observed every time there was a vacancy. They never came close to winning. But, through a stroke of luck, and a few acts of charity to open up the debate, the campaign slipped past the number of nominations required with only minutes to go, and his name went on a ballot of four candidates for the membership in the country to vote on. The rest, as they say, is history.

Following his improbable victory, Corbyn’s Labour swelled to become the largest political party in Europe as hundreds of thousands of enthused Brits rushed to support his for the many, not the few brand of politics. By 2017, Labour had over half a million members, an increase of over 200% since its historic low only a decade before. Reports from the party conference that September showed a base electrified with a rare excitement, rubbing their hands at the shiny new set of radical policies they were sure they would soon take into government. Labour was no longer going to kowtow to conservatives. The sight of Bernie Sanders, a similarly old and insurgent character rewriting the rules of American politics, only added to the sense of history being made.

To his supporters, Jeremy Corbyn is the Magic Granddad—a soft, affable old man, who makes his own jam, tends his allotment and would offer his vegetarian sandwiches to you on discovering you had nothing to eat (according to one former MP). Decades spent untempted (and uncorrupted) by power are proof of a morality that can’t be bargained away with high office. His long and virulent opposition to the Iraq and Afghanistan wars, South African apartheid, nuclear weapons and the Palestinian occupation show a man who champions the underdog at every turn.

It’s a compelling narrative and one that chimed with a large section of the British public when, in the surprise election of 2017, Corbyn increased Labour’s vote share more than any leader since 1945, winning 40% of the vote—only two points behind May’s Conservatives. Adding to the party’s seats and depriving the Conservatives of their majority was enough. It wasn’t a win, but it wasn’t a loss either. Next time, he only needed a swing of 1.5%—barely a hurdle at all against an adversary battered by eleven years in government. Theresa May had campaigned poorly, and daily pictures of them side by side on the news and social media had highlighted the veteran socialist’s best qualities. He could actually talk to people. He’d been doing this kind of thing for years, after all.

Britain’s generally right-of-center press has always given Corbyn a hard time, sometimes on poor grounds. But what small crumbs of goodwill there were have all but evaporated. His first two years of leadership were dotted with media events like softball profiles in broadsheet newspapers, attempts at playing Pokemon GO on the BBC, and guest appearances on Mumsnet talking about biscuits (“If forced to accept one, it’s always a pleasure to have a shortbread.”) As the years have passed, controversies piled up and Britain’s departure from the European Union looms larger, the UK’s prime-minister-in-waiting’s relationship with the press and his party have only deteriorated.

The last two years have been a fairly masterful balancing act on the part of Britain’s official Opposition. Whilst Corbyn’s Labour constantly emanates a liberal, internationalist, Remain-y vibe, keen to keep the bulk of its pro-EU membership happy (helped by the fact that the party’s elected politicians voted heavily for Remain), it has never meaningfully strayed from actually carrying Brexit out. For most of the past two years, a second referendum (or People’s Vote) has functioned as a particularly effective signaling tool. Labour wouldn’t rule it out was the line. As the possibility of a second vote disappears and Britain’s actual exit from the European Union pans into view, the party’s Europhiles are beginning to stir.

And there are a lot of them, too. The influx of Labour members that Corbyn’s election preceded brought in a number of tribes, almost all of whom unite under the term socialist, but come with their own pet issues and ways of doing politics. One topic that unites an unassailable coalition is Brexit: 72% think he should support another vote and 88% would vote to Remain if it happened. After previously pledging to give Labour members a greater say over party policy, the lack of even a superficial nod to the idea looks like a particularly insolent move.

A recently published clip from 2008 showing the Labour leader calling the EU a “European Empire” is a reminder of what Corbyn really is: a Leaver—a fact that becomes harder to hide as each day passes. It is far from certain that the liberal-left, who make up the party’s base, will forgive him for these crimes on the biggest issue in a generation. Brexit has forged a new binary in British politics, creating sides in a fierce culture war for which people demand advocates. Meanwhile, Corbyn continues to overrule the pro-Europe members of his shadow cabinet who attempt to exploit these realities, in bold defiance of his base and the new political reality.

Corbyn won’t budge though, because Corbyn doesn’t, and this is clear in every aspect of his politics. The ongoing crisis in Venezuela has dragged Corbyn’s long-standing affinity for left-wing dictators like Maduro, Castro—and, in the case of his Shadow Home Secretary, Mao—back into the limelight. A politician from a previous generation would have renounced his past flirtations with these characters as folly, at first whiff of a scandal. Much like Trump in the States, the obstinate Corbyn stands his ground, because he can.

Shortly after his sudden rise, the Labour Party cannibalized the political ecosystem to its left, absorbing a number of movements and activists whose outlook on the world was far more extreme. As a result, darker elements that most assumed were permanently gone from mainstream politics have once again reared their head. Chief among these demons is anti-Semitism—depressingly, an increasingly common sight in progressive or left-wing circles, and not just in the UK. If his belligerent anti-Europeanism is an unhealing sore, Labour’s culture of anti-Semitism under Corbyn is an open wound and one that has been festering for years.

Labour councilors and candidates have been discovered calling the Holocaust a hoax and referring to Jews as warmongers. Jewish Labour MPs have complained for months about torrents of abuse, much of it including Jewish slurs—often accompanied with a political point about the ongoing conflict in Israel/Palestine. The trope that being a Jew is synonymous with supporting Israeli government policy—or having a higher loyalty to Israel—is a common one in Corbyn-sympathetic digital spaces.

The man himself isn’t untouched by this. A year before he became leader, he attended a ceremony honoring the perpetrators of the Munich terror attack, which killed eleven members of the Israeli Olympic team. When footage re-emerged in 2018 he claimed he was “present… but not involved.” A comment that has been memed ever since. Comments unearthed on Facebook in 2015 show Corbyn defending an East London mural many claimed was anti-Semitic. Before being painted over, it showed six elderly white men, all with stereotypical Jewish features, playing Monopoly on the backs of black and brown men. To their left stands a man holding a sign saying The New World Order Is the Enemy of Humanity. Corbyn, of course, denies any and all accusations of anti-Semitism.

In April of 2016, a barrister and prominent civil liberties activist was commissioned to write an independent report into anti-Semitism in the party. The Chakrabarti Report—named after its author, Shami Chakrabarti—found that, although racism was not endemic in the party, there was “occasionally [a] toxic atmosphere.” Two months later, Chakrabarti was made a Baroness on the advice of the Leader of the Opposition and leader of the Labour Party, Jeremy Corbyn. Baroness Chakrabarti now sits in the shadow cabinet as Shadow Attorney General. Maneuvers like these have done nothing for Corbyn’s credibility on the issue.

Outside of his admittedly large, vocal and steadfast following, debates about whether or not Corbyn himself is an anti-Semite rage on. According to a February YouGov poll, 33% of the country believe he is, whilst 24% disagree. (34% said they did not know.) This feeling is even more pronounced in Westminster, where MPs and party staffers have observed an odd culture change—much of it taking place online—that has shocked even the most passionate of Corbyn acolytes.

And its pungent smell is turning off some of his earliest convertees, most of whom got involved with Corbyn for a nicer, kinder politics. Many are discovering something quite different. After the end of the summer of 2018, a third of those who voted Labour at the last election told pollsters they wouldn’t again. The damage has been less severe on the membership, though leaked numbers apparently reveal a drop of 10% since December 2017. The Labour party denies these figures.

This result is this week’s defection of seven MPs from the party, with many more expected to follow the now eleven parliamentarians who have formed the Independent Group. (It is worth pointing out that, legally, they are not yet a political party, although that is the declared direction of travel.) For older followers of British politics, this looks eerily familiar to the 1981 split in Labour that gave birth to the Social Democratic Party—later to become part of the Liberal Democrats. In the mythos of British left-wing politics, the split consigned the liberal-left to a generation in the wilderness, and gave Margaret Thatcher almost a decade in power, unthreatened by a divided opposition.

Polls out in the last few days (and the first to include the new Independent Group) show why the British center-left had reason to worry. Most of the group’s appeal is, unsurprisingly, among Labour-sympathetic voters. In some polls, the Conservatives now have a lead of over ten points. The important question—for Corbyn, Theresa May and the country—is whether enough will break away to hold the balance of power in the House of Commons. There is a small window: if an election is called soon, the new grouping will almost certainly lose most, if not all, their seats. The only twist is, Corbyn is more than likely to lose, too.