Some Americans are surprised that young Democratic primary voters have embraced Sen. Bernie Sanders, a self-identified socialist, by such a broad margin. And understandably so. After more than a century of obsessive anti-communism, capitalists thought they finally had the game all sewn up. But a portion of U.S. conservatives saw the phenomenon coming far in advance; a few of them have been warning about the rise of cultural Marxism for years. It’s time we give them a little credit.

Cultural Marxism is the boogeyman for much of what’s called the alt right — a narrow range of bigoted ideologies held predominantly by white men who oppose feminism, multiculturalism, political correctness and other progressive ideas. The fringe theorist William S. Lind usually gets credit for originating the idea during the first fights over political correctness a couple of decades ago. According to Lind and those he inspired, cultural Marxism is the result of the left’s failure to bring about revolution across the Western world in the first half of the 20th century. In their telling, a group of Marxist intellectuals fled Hitler, went to the United States and plotted a takeover of American culture. With multiculturalism, diversity and political correctness, their dastardly plot was accomplished.

Like all good conspiracy theories, there’s some fact and some fiction in Lind’s account. The Frankfurt school of intellectuals (including Theodor Adorno, Herbert Marcuse, Erich Fromm and others) did immigrate to the United States. And they have definitely had an outsize influence on some parts of American academic culture. Where the conservatives get confused is the relationship between these Marxists and Democrats. Lind and his followers see one big group of commies; actual commies, on the other hand, see liberal capitalist use of diversity rhetoric as a co-optation of our line, which is to say that two dads in a Cheerios ad is not part of a revolutionary strategy. Sure, gay marriage is legal, and marijuana is getting there. But Marxists don’t seem to have won much of anything in the run-up to the 2008 financial crisis, whereas capitalists won so much that a Sanders correction seems almost plausible.

The alt right sees Marxism’s retreat into the academy as a grand strategic feint. They forget the anti-communist purges that plagued American society from top to bottom. Only some parts of some universities were willing to shelter Marxists, and that’s where they reproduced. (It’s worth noting that this process has been extremely variable; each academic department at each school has its own ideological mix, and there are disciplines that are as clean of leftists as any Wall Street bank.) But as more and more young Americans enrolled in higher education and as Marxist cultural theory developed, some central left-wing tenets have taken hold outside the academy. And whether it’s called social justice warrior theory, cultural Marxism or feeling the Bern, these ideas have coalesced into a recognizable politics.