I recently warned that the campaign against Palmer Luckey, one of the creators of the Oculus virtual reality headset, was an ominous sign that Silicon Valley is adopting a Soviet-style code of all-pervasive political conformity.

The goal of the campaign against Luckey was to get his new boss, Mark Zuckerberg—Facebook bought out Oculus in 2014—to fire him. I’m guessing that’s not going to happen, because Zuckerberg has just offered a strong defense of another Silicon Valley political apostate, Peter Thiel.

A private post apparently to Facebook employees was leaked at Hacker News then publicized at BoingBoing and elsewhere, in which Zuckerberg explains why he’s keeping Thiel on Facebook’s board—Thiel was an early backer of Facebook and has been a longtime adviser to Zuckerberg—after Thiel announced he is backing Donald Trump’s presidential campaign with more than a million dollars of his own money.

Here is Zuckerberg’s reply:

Don’t take this idea of a “leak” too seriously. From the way the post was written, it’s clear that it was intended to be widely shared, and the last paragraph sounds like an ad for Facebook. So the “leak” was probably deliberate, or at least tolerated. Its authenticity was certainly confirmed by Facebook pretty quickly.

You can see why they would want it to be public. Zuckerberg needs to make people who lean to the right feel better about Facebook after the recent scandal about its Trending Topics function being biased against conservative sources. Well, mission accomplished. We do feel better about Facebook and about Zuckerberg.

Many of us on the right are not fans of Trump, but Zuckerberg is absolutely right that people can back the Republican nominee for different reasons, including totally normal ideological disagreements on issues like taxes, the size of government, and religious freedom. He’s even more right that the real test of tolerance is “standing up for the rights of people with different viewpoints” from your own. And he’s dead-on in skewering the Silicon Valley left’s hypocrisy on this issue: “We can’t create a culture that says it cares about diversity and then excludes almost half the country because they back a political candidate.”

Zuckerberg is a political “liberal” who backs Hillary Clinton. But occasionally American liberals remember that they are supposed to be liberal, i.e., pro-freedom. I remember for decades the old “liberals” complaining about “McCarthyism” and lecturing us about how terrible it was to deprive people of the ability to work in an industry because of their political views. The people they were talking about were Communists—advocates of a totalitarian ideology responsible for the deaths of 100 million people in the twentieth century. So these were hardly sympathetic figures.

Yet now the left has decided to impose a new McCarthyism aimed at far more mundane political differences.

Here, for example, is Cory Doctorow at BoingBoing referring to Thiel as a “major donor to white-supremacist/pro-rape presidential candidate Donald Trump.” I’m no fan of Trump, but this is an absurd description of what his candidacy is about. Later on, Doctorow compares supporting Trump to supporting Osama bin Laden. Can we extend Godwin’s Law to cover this?

Remember all those snide comments lefties used to make during the Cold War about how we were afraid of Communists hiding under our beds? I wonder if Doctorow is kept up at night by the thought of white supremacists hiding under his bed. Yes, the resurgence of racism is a serious problem, but this goes to the level of paranoia.

The immediate excuse for this is Trump’s boasting about being a serial groper, so that accepting him as the nominee of a major party will supposedly “normalize rape culture,” as Jason Putorti argues in a broadside against Thiel. But anyone who was actually concerned about “victim-shaming” and normalization of sexual assault would be equally appalled at the candidate who policed all those bimbo eruptions and helped smear Bill Clinton’s accusers as trailer-park trash. Since there is no attempt to ostracize supporters of Hillary Clinton—supporters like, you guessed it, Jason Putorti—we can conclude that sexual assault isn’t the real issue and that it’s being used as an ideological stalking horse for other political differences, or for the same old politics of my tribe versus your tribe.

A big part of our problem these days is that too many people have burrowed themselves into political monocultures, in universities, in their neighborhoods, and most of all on social media sites like Facebook, where the “unfriend” function nicely facilitates dissident purges. Not only is this self-isolation making us unable to function in politics, because we can’t deal with or understand political opposition, it also threatens to turn every aspect of life into yet another circular discussion where we’re all just confirming each other’s biases.

The role of Silicon Valley is to be an engine of innovation, and innovation doesn’t thrive under a regime of intellectual conformity, even if the people who impose it convince themselves it’s okay because they’re the good guys.

So congratulations, Mark Zuckerberg, for injecting some sanity and tolerance into an otherwise awful and bitter political year. Now if we could just talk about Trending Topics, because I hear you’re still having trouble with that.

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