The resignations of New York Times opinion editor Bari Weiss and New York Magazine writer Andrew Sullivan effectively punctuated a week in which the center-left press went to war with itself over the notion that the atmosphere they’d cultivated might not be the most conducive to free and open debate.

Both writers—centrist but heterodox insofar as they wrote for liberal publications while being sharply critical of the identitarian excesses and groupthink to which the left has succumbed—are frequent objects of abuse. Their views, which remain well represented within the Democratic coalition, are regularly anathematized by their “very online” colleagues in opinion journalism as “controversial,” “bigoted,” “racist” “reactionary”—even targets of the left’s “hate.” As Vanity Fair’s Joe Pompeo revealingly wrote, Weiss’s conventionally liberal “commentary often appeals to conservatives”—an unforgivable sin.

Criticism of their work bordered on (and regularly veered into) ad hominem. The suppression of their work within their institutions and the internal harassment to which they were subjected simply became too much. So, they will be taking their considerable talents elsewhere.

This mounting pile of dead canaries within the liberal coal mine has inspired not introspection but withering mockery and derision. You see, goes this response, there really is no such thing as “cancel culture.” These voices are free to go wherever they want, just so long as it’s somewhere they can be easily ignored.

There is a sickness settling over the center-left intellectual landscape. It is one the left could recognize when its symptoms were observed in their political rivals: the plague of “epistemic closure.” Bruce Bartlett described it as the condition in which an intellectual movement abstains from the necessary work of questioning itself. Rachel Maddow blamed the Republican Party’s 2012 losses on the “factual bubble” in which the conservative movement was cocooned. As the right’s more self-critical voices became “marginalized, even self-marginalizing,” Marc Armbinder observed, it would only settle deeper into a self-reinforcing feedback loop that would foreclose on the prospect of representing a majority constituency.

So, lefty projection on a massive scale, in other words.