The vibes have not been this good for a long time.

Only two weeks after President Joe Biden’s decision to end his campaign turned the 2024 election on its head, Vice President Kamala Harris has shocked the political establishment by choosing as her running mate Minnesota governor Tim Walz, the most progressive of the handful of names in contention. Walz has a record as governor that anyone on the Left has plenty to be pleased with, from putting in place free, universal school meals and paid family and medical leave to establishing a form of tuition-free public college and beefing up worker protections.

But that’s not what makes this pick significant.

Harris’s decision to go with Walz over Pennsylvania governor Josh Shapiro, the other name that her list had been whittled down to, is another major sign, on top of Biden’s 2020 campaign and the first year of his presidency, of a major shift in the United States’ political center of gravity since 2016, and a reversal in what passes for conventional political wisdom among the Democratic establishment.

Ever since Bill Clinton won the presidency by going out of his way to antagonize the left wing of his own party, Democrats have been guided by a simplistic philosophy: you win elections by tacking to the center on anything and everything, and ideally, you do it by making sure everyone saw you giving progressives a loud and painful slap in the face.

This is not what happened here. By almost every parameter of conventional Democratic thinking, Shapiro was the logical, “strong” pick for Harris: he’s a business-friendly centrist who wants to cut corporate taxes; he bucked unions on school vouchers, a favorite policy of the Right and neoliberal Democrats attempting to dismantle public schools; and he was vehemently pro-Israel, to the point of using state power to attack dissenters on US-Israel policy and comparing left-wing, antiwar protesters to the Ku Klux Klan. He was backed by big money, sometimes far-right pro-Israel and corporate donors, and choosing him was explicitly urged by centrist pundits as a way for Harris to publicly kick progressives in the shins.

Walz, meanwhile, is unabashedly progressive. He not only passed measures that were economically left but proved supportive of issues like gun control, abortion rights, and transgender rights. He has, to the chagrin of centrist commentators, said that “one person’s socialism is another person’s neighborliness,” expressed guarded sympathy for the message of pro-Palestinian protesters, and was endorsed by Sen. Bernie Sanders, the Senate’s only socialist. By the traditional Democratic playbook, all of this should have made him toxic.

And yet Walz’s left-leaning governance was reportedly his main selling point for Harris, who, despite being a career-long corporate-friendly centrist herself, seems to want to accomplish on the national level something similar to what Walz has done in Minnesota. At the very least, it was not viewed as a drawback that would undermine his demographic appeal as a white, male, rural-rooted, hunting-and-fishing Midwesterner.

In fact, Walz has in the end united an improbably diverse array of politicians associated with the Democratic Party, endorsed and reportedly backed behind the scenes by Sanders and Rep. Nancy Pelosi, respectively, while drawing eager plaudits from Squad members Reps. Alexandria Ocasio-Cortez and Ilhan Omar, all the way to centrists Dean Phillips, Hillary Clinton, and Joe Manchin.

Meanwhile, though the Harris camp says Shapiro’s problem was in a lack of chemistry, it’s hard not to think back to the avalanche of commentary in the past few weeks that pointed out how what in previous eras might have been counted as strengths had become potential liabilities for the Pennsylvania governor: his calls to cut the corporate tax rate clashed with Harris’s plans to raise it; unions’ dislike of him threatened to undermine a key and energized part of the Democratic coalition; and his uniquely bad record on Israel-Palestine threatened to reopen a festering wound within the party that they had managed to at least partially bandage over by getting Biden to drop out, especially after reporters unearthed a shockingly racist opinion piece he had written on the subject in college, and which the now fifty-one-year-old Shapiro didn’t even bother to address, let alone apologize for.

“I’m literally texting with a number of CEOs right now,” one MSNBC talking head told the decidedly pro-Shapiro Morning Joe panel this morning, not long after Harris had made a big push to win the favor of big business. “The business community . . . was hoping, maybe hoping against hope, that the governor of Pennsylvania would be the vice-presidential pick, and that was going to be a larger indicator or signal about how Vice President Harris would govern as president.”

Of course, we shouldn’t overstate things. There really are endless variables involved in a decision like this: Walz has a unique profile, in his strengths as a communicator, his specific demographic profile (namely his rural, blue-collar, non-elite-educated background), and as a formerly centrist lawmaker who took on the progressive mantle late in the game, all of which blunts attacks on him as an of out-of-touch radical. And Shapiro had other liabilities beyond his centrism, including his role in a sensational case involving a possible murder that had been allegedly wrongly ruled a suicide, that the state supreme court only just decided to take up this year, and which he has been accused by the victim’s parents of “sitting on.”

Still, it’s hard to see any of this — Walz’s transformation into a progressive, his unapologetic defense of his record, and it being considered an asset over a centrist rival — happening in an earlier era of US politics. The fact that it comes after Joe Biden, one of the leading engineers of the Democratic Party’s rightward turn, briefly governed as a progressive populist is solid proof that the American political landscape has markedly changed.

At the start of this millennium, Biden himself pointed to Clinton’s winning campaigns to trash the idea “that class warfare and populism is the way we should conduct the next election.” It seems Democratic Party leaders no longer wholly agree.