But the unexpected outcome could produce new forms of conventional wisdom as misleading as the flawed punditry that enticed May to call the election in the first place.
It didn't need to happen, because May had three years left in her term. Voters clearly resented being called to the polls for opportunistic reasons. May thought that because Corbyn was so unpopular and seemingly out of the mainstream, she could turn a relatively small Conservative Party majority into an overwhelming advantage in Parliament. She also thought she could marshal the nationalism reflected in Britain's vote to leave the European Union by adding the far-right votes of the UK Independence Party to Conservative totals.
May forgot that 48 percent of British voters rejected Brexit and were still not happy about the outcome. They were looking for ways to strike back, and they did.
She and just about everyone else also underestimated how skilled a campaigner Corbyn would be. For example, Chuka Umunna, one of Corbyn's critics among moderate Labour parliamentarians, acknowledged that Corbyn ran a "positive and dynamic campaign" that emphasized hope. The Economist, no friend of Corbyn's, conceded that he "fought a strong campaign against all expectations." The more sympathetic Observer credited Corbyn with achieving "a sensational result for Labour."
Lord Stewart Wood, who was a top adviser to former Labour Party leader Ed Miliband, saw Corbyn's strong showing as the definitive end of "Blairism," the middle-of-the-road Labour politics associated with former prime minister Tony Blair.
In a telephone interview, Wood noted that Corbyn rode "a tide turning against austerity" after years of Conservative budget cuts. Like Bernie Sanders in 2016, Corbyn had mobilized an energetic grass-roots campaign and sophisticated social media network, Wood said.
And far from working politically in favor of the Conservatives as the traditional party of order, the terrorist attacks before the election hurt May. Corbyn's criticisms of May's cutbacks in the police forces, Wood believes, were particularly resonant because they linked the Labour leader's argument against austerity to the issue of security. He added that many voters he encountered while campaigning door to door were "absolutely furious" over President Trump's verbal assault on London Mayor Sadiq Khan after the London Bridge attack.
Matt Browne, who was an aide to Blair and is now at the Center for American Progress in Washington, agreed that Corbyn's showing meant that for the "foreseeable future, centrist progressivism is on hold." The more moderate left, he told me from London, needed to learn from "what Corbyn accomplished, especially in mobilizing the young."
But given May's unpopularity, Browne argued, "this is an election we could have won, and could have won handsomely." There is some evidence, particularly in anti-Brexit London, that more moderate Labour candidates such as Umunna ran ahead of the national swing.
Thus the twin caveats to sweeping conclusions on the left: Its more moderate wing needs to acknowledge the mobilizing power of a clear and principled egalitarian politics and the increasingly progressive tilt of younger voters. But fans of Corbyn's approach to politics need to come to terms with the fact that although he outran expectations, he lost the election. Labour still needs a strategy for winning dozens of additional seats.
Britain also defied trends in other Western countries toward the fragmentation of older party systems. This continued on Sunday in France, where President Emmanuel Macron's year-old party surged past long-established rivals to its left and right in the first round of legislative elections.
In Britain, by contrast, Corbyn boosted the Labour Party vote to 40 percent, 9.5 points higher than it was two years ago. And even though the election was a disaster for May, the Conservative vote rose to 42.4 percent, a 5.5-point increase. It was the highest Labour share since 2001 and the highest Conservative share since 1983. The sharp decline of the Scottish Nationalists — they lost more than a third of their seats — further signaled a return to an earlier political era.
In other words, claims that everything has gone haywire in Western politics since Brexit and Trump's election are exaggerated, as we are also likely to see in the German election this fall. And backlashes to Trump continue to push electorates in Europe toward the center or left. This certainly played a role in Macron's victory in France last month and continued to strengthen his middle-of-the road political movement in Sunday's voting.
As for May, she sought to recast British conservatism in a moderately nationalist way. It might be seen as Trump-lite, with more coherence than the American brand. She hoped to hold the metropolitan professionals while expanding her coalition to a restive working class far from the centers of power. It was a bold bet. But it failed.
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