Facebook founder and CEO Mark Zuckerberg grappled with questions of all stripes at Tuesday’s Senate hearing on the social media platform and the 2016 election, but it was Nebraska Republican Senator Ben Sasse’s questions about hate speech that should alarm free speech advocates.

Along with inquiries from Texas Republican Ted Cruz, Sasse stood out. His portion began by acknowledging that companies like Facebook “have a hard challenge” when it comes to creating their own rules in addition to government regulations.

That being said, Sasse told him that he acknowledges yet worries about private groups like Zuckerberg being able to “make policies that maybe less than First Amendment-full spirit embracing” and “go from violent groups to hate speech in a hurry.”

Sasse then asked the key question:

You may decide or Facebook may decide it needs to police a whole bunch of speech that I think America might be better off by not having policed by one company that has a really large and powerful platform. Can you define hate speech?

Despite the fact that Zuckerberg repeatedly mentioned how he hopes social media companies like his will rely on Artificial Intelligence (AI) to clear out hate speech, he couldn’t define what hate speech is:

ZUCKERBERG: Senator, I think that this is a really hard question and I think it’s one of the reasons we struggle with it. There are certain definitions that — that we — that we have around, you know, calling for violence or — SASSE: Let's just agree on that. ZUCKERBERG: — yeah.

Sasse stepped in to end this cringeworthy response, emphasizing that “[i]f somebody’s calling for violence, we — that shouldn’t be there” but what he was trying to ask him about concerned “the psychological categories around speech.”

The Nebraska Republican continued to hammer home this danger about how scores of younger Americans are embracing the erosion of the First Amendment and censoring pro-lifers:

You use language of safety and protection earlier. We see this happening on college campuses all across the county. It's dangerous. 40 percent of Americans under age 35 tell pollsters they think the First Amendment is dangerous because you might use your freedom to say something that hurts somebody else’s feelings. Guess what? There are some really passionately held views about the abortion issue on this panel today. Can you imagine a world where you might decide that pro-lifers are prohibited from speaking about their abortion views on content — on your platform?

Zuckerberg shot back that “I certainly would not want that to be the case” but Sasse countered: “But it might be really unsettling to people who have had an abortion to have an open debate about that? Wouldn’t it?”

“It might be, but I don't think that...would fit any of the definition of what we have, but I do generally agree with the point that you're making which is as we're able to technologically shift towards especially having AI proactively look at content, I think that's going to create massive questions for society,” he in part responded.

Sasse concluded by reiterating that it’s clear that violence plus human and sex trafficking “have no place on your platform, but vigorous debates, adults need to engage in vigorous debates.”

To see the relevant transcript from April 10's Joint Senate Judiciary and Commerce Committee Hearings, click “expand.”