The former New York mayor Michael Bloomberg is seriously considering running for president as a Democrat – a prospect that has horrified many progressives. At a time when the Democratic party appears to be moving swiftly to the left, the candidacy of a white, centrist Wall Street billionaire feels like a big step backwards.

But a Bloomberg run should ultimately benefit the left more than hurt it. Between his stale politics, his stiffness as a campaigner, and his identity as a restrained elite in an era of raucous populism, Bloomberg’s bid to secure the Democratic nomination seems destined to fail spectacularly. More importantly, the pushback he’d experience on the campaign trail would help the left form clearer standards for more viable candidates – and indict the Democratic establishment that helped get us into the mess we’re in today.

The Democratic party – and progressive politics more broadly – have changed a great deal since he left politics

As one of the richest men in America, Bloomberg has a colossal war chest, an ego to match it, and substantial name recognition. But he’s also woefully out of touch with the political moment: the Democratic party – and progressive politics more broadly – have changed a great deal since he left politics five years ago.

Bloomberg is bound to face a big #MeToo reckoning on the campaign trail. Dozens of women have accused Bloomberg and his company of creating a hostile work environment for female employees. One lawsuit from the 90s claimed that Bloomberg responded to a female employee reporting that she was pregnant by declaring, “Kill it!” (Bloomberg has denied this.) More recently, Bloomberg has expressed doubt about the veracity of #MeToo accusations, saying that he doesn’t “know how true” all of them are.

Bloomberg’s past treatment of women is just one of many new vulnerabilities he has with a Democratic base that has raised the bar for treatment of marginalized communities. He would also take heat for his administration’s use of stop-and-frisk police tactics, which involved stopping people on the street to search them for guns, a policy that resulted in systematic racial profiling of black and Latino New Yorkers. Recently he defended the practice as necessary for bringing down crime, even though New York’s crime rate has fallen since the practice was ended and the Black Lives Matter movement has stigmatized such practices among progressives.

Bloomberg eyes 2020 presidential run as a Democrat, but can a centrist unite the party? Read more

And on the economy, too, Bloomberg seems to be a man of yesterday. At the 2016 Democratic national convention, he chided Democrats for inattention to deficit reduction and a tendency to “wrongly blame the private sector for our problems”. He also continues to defend Wall Street from stringent regulation. But polling data shows that among Democrats there’s huge appetite for government interventions in the economy in the form of Medicare-for-all and a federal jobs guarantee; in fact, a recent Gallup poll found that Democrats are now more fond of the idea of socialism than capitalism. It seems doubtful the base will be inspired by a banker-friendly billionaire who thinks that the key to success is taking fewer bathroom breaks instead of building a fairer economy.

Should Bloomberg undertake a sustained campaign for the Democratic nomination, he will in all likelihood became a lightning rod for the progressive wing of the party. Just the way that in 2016 Black Lives Matter relentlessly – and successfully – pushed Democratic candidates to adopt radically more progressive criminal and racial justice platforms, this time around, activists and advocates will probably target Bloomberg on his past treatment of women, his criminal justice policies, and his ties to Wall Street. Whether or not Bloomberg repents, the left will have crystallized new benchmarks for winning over the base.

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This ultimately should help deal a serious blow to the old guard of the Democratic party. That may sound counterintuitive: Bloomberg has previously registered as a Democrat, a Republican, and an independent, and he’s supported politicians from both parties. But in reality, he almost perfectly typifies the Democratic worldview that became dominant in the 1990s, when the party’s leaders believed that they could only win power by operating as centrists and presenting themselves as independent-minded technocrats. That paradigm prevailed among the party establishment until 2016, when Hillary Clinton lost to Donald Trump and Bernie Sanders became the most popular politician in America, tearing a hole in the party’s conventional wisdom about what the base wants.

Bloomberg’s policy record and his pride in masking overt expressions of ideology represents that old worldview – as Al Sharpton recently said, a Bloomberg run would be “a billionaire version of Bill Clinton”. Indeed, the parallels between the two are striking: a history of treating women inappropriately, a dangerous deference to banks, and a disturbing record on fighting crime. All signs suggest that the Democratic base knows it’s time to say goodbye to all that.