Last night, in a historic election, the UK Conservative Party celebrated its most sweeping victory since Margaret Thatcher, the original “Euroskeptic,” won the election for Prime Minister in 1987. The election had been regarded as particularly momentous, given the UK’s recent struggles to bring the much-debated Brexit to fruition. The Conservative Party won 364 seats in UK Parliament, compared to Labour’s 204, catapulting Conservative leader Boris Johnson to the position of Prime Minister. It was the worst defeat for Labour since 1935.

But in addition to Brexit woes, the election was also saddled with the baggage of the UK Labour Party and its controversial leader, Jeremy Corbyn. Over the past several years, Labour has been mired in accusations of anti-semitism, which seemed to plague both its members and leaders. The accusations culminated in nearly a dozen members of the party opting to defect in protest of Corbyn’s incapacity to deal with what many felt to be a rising culture of toxicity within Labour.

Just last week, a leaked memo written by Jewish Labour members to the Equality and Human Rights Commission (EHRC), the UK’s official regulatory body devoted to issues of discrimination, revealed the depths to which both the party and Corbyn had minimized, dismissed, or simply ignored accusations of anti-semitism within Labour, often identifying such criticisms to be a “right-wing smear.” Several times in an interview with BBC’s Andrew Neil last month, Corbyn failed to offer any sort of substantive apology, even when confronted with the statistic that nearly a half of British Jews were “seriously considering” leaving the UK, should Corbyn win the election.

There were other problems with Corbyn, too. As documented here, the Labour leader has a long history of palling around with terrorists, attending their conferences, referring to them as “friends,” and laying wreaths on their graves. Corbyn’s behavior could only be regarded as the seediest form of anti-Westernism, not one that posits anti-Western sentiment within a philosophical framework, but one that finds manifestation in friendships with those who seek the West’s destruction.

Corbyn was also a full-blown socialist in the way that U.S. progressives could only dream of, advocating for nationalization of most public services and some large national industries, nuclear disarmament of the UK, staggering increases in taxes on the wealthy, and softening tactics on combatting terrorism. Corbyn would have been the first self-identified socialist to lead the United Kingdom in 40 years.

But Corbyn’s dreams were swiftly dashed in an election whose results brought a sigh of relief to many. But lingering questions remain as to how the country formerly led by Winston Churchill could ever have come so close as to falling in the hands of a socialist, anti-Semitic, terrorist-sympathizer.

The crushing defeat of Corbyn, while reinvigorating for the project of Western democracy, may be a warning bell for the American Left, who continues to toy with the policies espoused unequivocally by Labour—including their affection for anti-Semitism. If the Left’s meltdown this week in response to Trump’s Executive Order protecting Jewish college students is any indication, there doesn’t seem to be much consensus on the Left regarding what is more important—hating Trump or combatting anti-Semitism.

After witnessing this election unfold, it became abundantly clear that the base of the American Democratic Party and the base of the UK Labour have a disconcerting amount in common. Both identify as radically progressive and encourage government control over vast swaths of major industries. Both embrace identity culture wholeheartedly, with the equality message nearly always excluding Jews in some fashion. Both espouse anti-Israel rhetoric, often using it to cloak blatantly anti-Semitic sentiments. And both seem to have a stark antipathy to the project of Western democracy that manifests itself in disturbing way—namely, in calls for the allegedly rotten project itself to be utterly destroyed and refashioned into some utopic vision that the socialists have cooked up.

Following the election, many leftists took to Twitter to console themselves that the fate of Labour would not be the fate of the Democratic Party, searching for any meaningful distinction between Corbyn and the progressive swivel of the American Left. Indeed, the desperation was quite telling for those of us who have been reporting on the parallel lives of the two movements for nearly a year.

UK voters have spoken. In response to one of Labour’s worst defeats, Corbyn has opted to step down as leader of the party, fielding a litany of accusations from within Labour that he is to blame for the disastrous outcome.

However, Alastair Campbell, a former adviser to Tony Blair and Corbyn rival, emphasized that last night’s results were not simply a referendum on Corbyn but on Labour’s vision to upend the entire British economy. “Labour has to face some hard truths — this was not just about Corbyn but the broader worldview and an economic plan that so many people did not believe,” Campbell tweeted.

It’s unclear what comes next for Labour and if the party will pivot back to the center in an attempt to recapture the days of Tony Blair. With no clear successor to Corbyn, the party seems ripe for a refashioning of its own. In the meantime, it would be wise for American Democrats to take stock of their own progressivism and heed the warning put forth by the UK election. Indeed, as UK voters show us, it’s possible that not everyone is ready for their anti-capitalist, anti-Western utopia.