The tilt-a-whirl of American politics keeps spinning, and there seems no way to slow it down.

Consider the juxtaposition: We have a president who responds to the most widespread and sustained expression of popular protest against racial injustice in decades by repeatedly tweeting "LAW AND ORDER," spreading a conspiracy theory to justify a blatant act of police brutality, and scheduling photo-ops so he can cosplay Mussolini — all the while anarchists take over parts of cities with no pushback from elected officials and roving bands of iconoclasts take it upon themselves to tear down and deface public monuments.

At the moment the left thinks all the momentum is on its side. In the short term, that's probably true. Donald Trump's approval rating is heading south and his disapproval rating is spiking. This has left him with numbers that will likely render him a goner in November if trends hold. In many ways, it's a replay of how the public reacted to the president's abysmal response to white supremacist violence in Charlottesville, Virginia, in August 2017. Trump languished at his polling low point for most of that month and stayed close to that bottom for the rest of the year. If events unfold similarly this time around, he will not survive.

These trends, combined with polls showing a big, rapid shift in the direction of support for Black Lives Matter, are convincing some on the left that the dam has finally broken — that years of quasi-fascist trolling by Trump has triggered a long-hoped-for lurch to the left in public opinion.

But this is premature. The far more likely scenario is that the left will overreach — indeed, that it already has — and that even if a sizable portion of the electorate decides that it's time for Trump to go in November, this shift will be followed by a rapid rebound in the other direction. That's because we now live in an era of polarization and centrifugal ideological forces that aren't just going to be dissipated by a single electoral repudiation of the Republicans.

Such is the dynamic in a time of tilt-a-whirl politics that a big landslide for the left might actually be the best possible scenario for the GOP, just as Trump himself was rocket fuel for Democrats in 2018 and perhaps this year as well. That's because while Trump has practiced and shown the electoral viability of a harder right form of politics, his distinctive incompetence and malevolent narcissism have made him an atrocious president by any measure. A Trump trouncing in 2020 would enable the GOP to coalesce around a less flamboyantly terrible model of leadership for the future of the party and the country. Tom Cotton, Nikki Haley, Mike Pompeo, Mike Pence, Marco Rubio, Tucker Carlson — any of these and possibly many other potential presidential candidates would be nicely set up by a Trump defeat for a strong run in 2024.

But that scenario will not only be rendered more likely by Trump getting booted from the White House in November. It will also be advanced by the left overplaying its cards.

The better Biden and his party do in November — the more power they win in Washington — the more the activist-driven left wing of the party will expect big political payback from the incoming administration. And this won't primarily be from the democratic-socialist faction of voters and activists who swooned for Bernie Sanders. (That economically focused form of leftism would have a modest shot of accomplishing a realignment of our politics if the faction's proposals for significant economic reforms were combined with a somewhat more moderate stance on social issues.)

Instead of a big Biden victory empowering the socialists, it will be left-wing culture warriors who feel emboldened to practice a politics of grand symbolic gestures and bold sloganeering on a national stage — think of today's toppled Christopher Columbus statues and calls to "defund the police" — and do their best to pull the new president in their direction. Assuming Biden's recent leap in the polls gets consolidated, leading to a solid win or a landslide, this faction will make the case that it deserves the credit for Trump's evisceration and won't hesitate to play hardball to extract concessions, using its hard-earned moral authority and threats of political reprisals (withholding support in Congress for administration priorities) to get what it wants. Any sign of Biden adopting their full cultural agenda will run the risk of weakening the president's hand, since that agenda is popular within the Democratic Party only among social-justice activists and white urban progressives, and it is broadly unpopular in the country at large.

The result of a big Biden victory is therefore likely to be more full-tilt politics — with the Democrats moving further left than nationwide public opinion would justify. This will involve reversing Trump's reversals of Barack Obama's policy accomplishments and pushing far beyond them, which will in turn set up a big win for Republicans in the 2022 midterm elections and render the re-election campaign of the by-then octogenarian Biden (or the campaign of his vice president, if he bows out after one term or dies before its conclusion) highly vulnerable.

And if the GOP does manage to win in 2024 with a right-wing populist more competent and capable of enacting policy than Trump? That would of course set up a series of reversals of Biden's reversals of Trump's reversals of Obama. Which would make the first post-Trump Republican president vulnerable to the next whiplash-inducing turn of the tilt-a-whirl.

That is where American politics has ended up in first third of the 21st century, with a series of wild ideological swings, each propelled by the last and propelling the next — and no one able to figure out how to get off or stop the ride.