Keir Starmer’s resignation after electoral defeats and plunging support is being seized as a cautionary tale by opponents of “moderation” in the U.S. Democratic Party—even as supporters argue the picture is more complicated and tied to economics and governance
The week the resignation came, it didn’t just end a British premiership. It handed U.S. Democrats a fresh argument—one that lands hard in party rooms still wrestling with what “moderation” is supposed to solve.
After Donald Trump’s 2024 victory. Democrats have been locked in a brutal internal conversation about whether the party has moved too far to the left on cultural issues. including immigration and trans rights. and whether it needs to tack toward the center to secure its future. Their opponents say that strategy would only alienate core Democratic voters without actually winning over MAGA.
This week’s spark for the anti-moderation camp wasn’t a new American development. It was the resignation of UK Prime Minister Keir Starmer.
Starmer, the argument goes, is the closest real-world test of the pro-moderation pitch. More than any other center-left figure globally. he appeared to execute the idea: moving the Labour Party toward the center on social issues. especially immigration. But then his numbers collapsed. Labour suffered humiliating defeats in special and local elections, while both the far right and far left surged.
“Starmer’s resignation is a warning,” political scientist Adam Bonica of Stanford University wrote this week. “In a moment like this, tacking right isn’t the safe play, it’s the thing that sinks you.”
Moderation supporters push back with a different reading: that Starmer didn’t win power in spite of moderation—he won power because of it, and his decline after taking office has more to do with economic fundamentals than culture.
“His cultural moderation has been an asset to Labour in getting closer to where the mainstream of voters are,” Claire Ainsley, a former Starmer adviser and current director of Project on the Center-Left Renewal at the Progressive Policy Institute, told me.
The evidence, as presented here, cuts against anyone claiming a clean moral victory. Starmer’s rise shows moderation can carry an upside. His downfall shows it can also turn into a trap—especially when a party’s centerward turn becomes its governing strategy rather than a perception-management tool.
When the Labour shift appeared to work, it was tied to a very specific problem: what voters thought the party was. After the UK’s 2019 elections, Labour was in the wilderness, led by the hard-left socialist Jeremy Corbyn. In that era, Labour suffered its worst performance in roughly 100 years.
The collapse wasn’t simply because the Conservatives were popular. Prime Minister Boris Johnson had a net approval rating of minus 12. Corbyn, by contrast, was at negative 40. Contemporary polls showed him as seen as unfit for office, with many of his policies believed to be unrealistic. Corbyn’s long record of foreign policy radicalism, along with scandals about antisemitism within Labour, contributed to that perception.
When Starmer won the Labour leadership contest in 2020. he pursued what British political scientist Simon Griffiths described as “decontamination”—a conscious effort to reposition Labour as part of the UK political mainstream. Starmer apologized for Corbyn’s handling of antisemitism. endorsed an increase in defense spending. and began openly mocking his predecessor as out of touch with ordinary Britons.
Griffiths writes in the paper that Starmer’s strategy was “a pursuit of ideological quietism to distance himself from Corbyn and reach out to more socially conservative voters who would be wary of this rhetoric.”
In the short term, the results looked like vindication. In the 2024 election. Labour won nearly two-thirds of the seats in the UK parliament—the third-largest majority in the party’s long history. There is evidence Starmer’s moderation helped. Voters who switched from the Conservatives in 2019 to Labour in 2024 were vastly more likely to say Labour respected people like them under Starmer rather than Corbyn.
But two caveats complicate the story. First, it isn’t obvious how much Starmer’s relative moderation mattered in the ultimate outcome. By then, the Conservative Party had been in power for 14 years and its reputation was in shambles. Data from YouGov showed Labour supporters were overwhelmingly more likely to cite getting rid of the Tories rather than affirmatively backing Labour as the chief reason for their vote.
Second, there is little reason to believe Starmer’s moderation on cultural issues—specifically immigration and trans rights—was decisive. YouGov’s 2024 data shows Labour voters’ top issues were overwhelmingly economic, including cost of living and healthcare.
So moderation may have helped, but not necessarily in the narrow way the U.S. debate is arguing about it.
Once in office, Starmer’s challenge was different: governing. Nearly everyone agrees his numbers began to drop because he failed to deliver the substantive quality-of-life improvements he promised.
“There’s been no respite on the cost of living. with particularly food and energy inflation remaining high. while the NHS [National Health Service] and public services have not really improved. ” YouGov’s Dylan Difford wrote this week. Labour “has ignored that many of its most glaring issues are the complaints common across all of their losses — the cost of living. public services. feelings of a lack of delivery and change — the key issues that helped Labour into power in the first place.”.
The question then becomes whether Starmer’s tack to the center on cultural issues softened the blow—or made it worse. The evidence presented here points toward the latter, particularly on immigration.
In the summer of 2025, Starmer delivered a high-profile speech laying out an aggressive new approach. He argued that mass cultural change was turning Britain into an “island of strangers.” Starmer announced an intention to significantly cut the number of legal immigrants entering the UK. The policy package included new limitations on foreign student admissions and a crackdown on asylum rights. Those changes delivered the promised cuts: by May 2026, net migration had fallen to the lowest number since the Covid-19 pandemic.
Even with the cuts, Starmer’s numbers kept falling.
Reform UK, an extreme anti-immigration party, surged and became the most popular party in the country and the odds-on favorite in the 2029 election. Disillusioned left-wing voters defected en masse to the Green Party, a former fringe party that took an unapologetically pro-immigration stance.
“They didn’t win back those voters that left for reform — and they alienated progressives,” political scientist Tarik Abou-Chadi of Oxford told me.
Abou-Chadi and others in his field describe this as a common pattern in European politics: on average. center-left parties that tack to the right on immigration don’t tend to win over voters who previously supported far-right parties. But they do tend to lose voters to left-wing parties that offer more to the cultural left.
A study described here offers unusually good evidence of that dynamic in Starmer’s case. Eight researchers measured how voters’ attitudes toward Labour changed after the “Island of Strangers” speech. They found the speech did some of what Starmer intended. Voters perceived Labour to be tougher on immigration after the speech than before.
But the perception didn’t help electorally. The authors conclude the speech “decreased voting intentions for Labour by 1.2 percentage-points and resulted in a 3.9 percentage-point haemorrhage in support from Labour’s own former voters without attracting any new supporters.”
It’s tempting to see Starmer as a slam-dunk argument against the idea that Democrats need to moderate in the United States. The thrust here is directionally correct, but it requires more nuance—and that comes down to how American and British politics are structured.
The UK system allows third parties to run and succeed: not only Reform and the Greens, but also the center-left Liberal Democrats, the Scottish National Party, and the new radical right faction Restore Britain. Voters dissatisfied with Labour from the left have options.
In the U.S., left-wing Americans have fewer realistic exits. They either vote for whichever Democrats nominate or throw their vote away, effectively helping the GOP. That makes it less likely—though not impossible—that tacking toward the center would cost Democrats a huge chunk of their base in the same way it cost Labour.
The American system also gives individual legislators more autonomy than the UK’s disciplined parliamentary system. That means individual members can build their own brands that reflect ideological moderation—examples cited here include Republican Senator Susan Collins in Maine and Democratic Rep. Marie Gluesenkamp Perez in her conservative Washington district.
So the takeaway from the Starmer experience isn’t that moderation is always doomed. It’s that successful moderation is more complex than picking the positions that appeal most to the median voter and replicating them as strategy.
When Starmer’s moderation worked, it wasn’t because Labour became identified with a specific set of moderate policies. It worked because he cultivated a perception—a vibe—that Labour was no longer the same party it was under Corbyn. His team corrected a sense that Labour was out of touch with highly visible actions.
Where it broke was when that approach became the governing formula.
The focus on poll-tested cultural policies designed to win over voters lost to Reform was premised on what the account calls a myth—that large numbers of far-right voters were open to voting for the center-left. It also meant compromising Labour’s image in ways that made Starmer seem both inauthentic and unprincipled. as if Labour under him was trying to be something it wasn’t and couldn’t be.
Those changes might have been survivable if Starmer had a new political identity ready to replace them. Instead, the account says he struggled to articulate a new North Star for the party and for his personal brand of politics to attract an enthusiastic base.
“Positioning himself as the custodian of a phantom center, Mr. Starmer treated most Labour supporters with contempt. as a partisan inconvenience and an obstacle to his project of national renewal. ” British journalist Samuel Earle wrote in the New York Times in May. “Yet he has also seemed too nervous to outline what that project might be.”.
That may be the most salient lesson for American politics in the wake of Starmer’s fall: whichever direction a party moves—left or center—compromising its core identity is almost certainly a losing strategy. Political parties need affirmative visions that animate supporters and clarify what they stand for.
Moderation can contribute to that kind of vision. Bill Clinton and Tony Blair had versions of it in the 1990s. But Keir Starmer, in this telling, didn’t—and Labour paid the price.
Keir Starmer Labour Party immigration moderation Democratic Party United States politics UK elections Reform UK Green Party Alex ideas trans rights political strategy