This is the season for columnists to offer some new idea that encapsulates the year that was. I got nothing. But 2023 was the year I finally abandoned my opposition to an old idea — the horseshoe theory of political ideologies.

The term is often attributed to French author Jean-Pierre Faye’s 1996 book “Le Siècle des idéologies” (“the century of ideologies”), but the concept is much older. It basically holds that the extreme right (“fascism”) and extreme left (“communism”) bend toward each other like the ends of a horseshoe.

While I’ve always thought totalitarian regimes — Stalin’s Russia, Hitler’s Germany — have more similarities than differences, I didn’t believe that the horseshoe theory mapped well in the American context. For starters, it depends heavily on the European understanding of the left-right ideological continuum (literally derived from the seating chart of the French National Assembly). In contrast to the Anglo-American tradition, in the continental tradition, right vs. left fights were more about how to use state power, rather than how to limit it. Statism just wasn’t much of a dirty word for either side.

Meanwhile anti-statism, including an ornery passion for civil liberties — i.e. classical liberalism — has always been a core component of American exceptionalism. Indeed, left and right in U.S. politics often become less statist as they become more extreme. This is a familiar observation about the right. Wanting to abolish government agencies, privatize or deregulate state functions, was long a hallmark of the American right; it’s hard to see how becoming more libertarian makes you more “fascist.”

But the American left has an anti-statist streak, too. For instance, defunding the police, legalizing drugs, open borders, decriminalizing prostitution, abolishing the “prison industrial complex”: These are more anarchic ambitions than statist. True communists like their cops and prisons.

In short, while the American left and right have always had plenty of disagreements, they were usually hashed out within the framework of America’s deep-seated classical liberalism. But what happens when the extremes abandon that liberalism? They start looking awfully similar.

For instance, few extremists from either pole really oppose cancel culture or censorship, they just want the ability to cancel or censor people or ideas they don’t like. Donald Trump is a zealous advocate for his free speech rights, but holds nearly opposite views for his critics.

The left and right may see huge differences between left-wing identity politics and right-wing identity politics — and there are huge differences — but it’s still identity politics, and the notion that individuals should be judged by what groups they belong to is profoundly illiberal.

Perhaps the most discomforting convergence is over the Constitution. It may offend some of its detractors to hear it, but The Federalist Society, with its deeply conservative and passionate commitment to constitutional fidelity, has always been a bulwark of classical liberalism because the Constitution is a quintessentially liberal charter. Indeed, that’s why Trump has reportedly turned his back on disloyal Federalist Society lawyers, many of whom wouldn’t aid Trump’s effort to steal the election. He now favors MAGA pettifoggers happy to treat the Constitution like an illegitimate law they can help their client wiggle out of.

There’s even a new right-wing project called “common good constitutionalism” which seeks to dethrone The Federalist Society and abandon constitutional originalism in favor of a results-driven approach to the law and the Constitution.

Some on the left might object, but from my perspective as a traditional conservative, that approach mirrors the left’s invocation of a “living constitution” to defeat constitutional interpretations it doesn’t like.

Of course, these trends predate 2023 by quite a bit. But what’s changed is how much more willing the political center is to let itself be defined by the logic and rhetoric of the extremes. The result is a kind of bipartisan consensus around the more European idea of fighting for control of the state, led by fairly mainstream politicians terrified of their party’s bases.

Why the rhetoric of the fringes has become mainstream probably has a lot to do with the changing media landscape and weakness of parties. But what remains constant is the importance of rhetoric itself, which, as the late literary critic Wayne Booth said, is “the art of probing what men believe they ought to believe.” And the loudest voices are bending the arc of our politics toward illiberalism.

Jonah Goldberg is editor-in-chief of The Dispatch and the host of The Remnant podcast.