Moderators Martha Raddatz of ABC and Anderson Cooper of CNN appear during the town hall debate at Washington University on October 9

When Martha Raddatz needled Donald Trump’s apparent lack of knowledge about American foreign policy on Sunday, it was an unusually aggressive approach for a presidential debate moderator. The tactic stood out even more given the event’s billing as a town hall showcasing questions from “undecided voters.” Still, ABC’s chief global affairs correspondent ultimately added more value by stepping in.

The power dynamics of who tells the story of campaigns is quickly shifting in favor of politicians, a change that holds the potential to make debate moderators the primary point of direct contact between presidential candidates and the media. The Republican nominee has shut out the mainstream press corps in recent weeks. And more aggressive than usual questions on Sunday night—by both Raddatz and co-moderator Anderson Cooper–provided an effective stand-in.

Audiences for debates tower over those of all other political coverage in an age of increasing media fragmentation, upping both the potential and risk of more assertive moderating. But Raddatz, with her subject-matter expertise, proved that such hands-on direction can ultimately lead to a more revealing look at the candidates than the public would otherwise get.

After Raddatz relayed an audience question about the humanitarian crisis in Syria, Hillary Clinton replied with a familiar argument for a no-fly zone, closer work with regional partners, and wariness toward an increasingly assertive Kremlin. Trump filled his two-minute response with a meandering critique of American nuclear capabilities, the crumbling of Libya, and the the US nuclear deal with Iran. Raddatz cut in to repeat her initial question, and the two shared a tense exchange in which the moderator’s interjections grew increasingly incredulous. Watch the clip below:

The topic was right in Raddatz’s wheelhouse: She’s a veteran foreign affairs reporter. And while her performance was widely lauded among journalists, scattered criticism from conservatives speaks to evolving expectations for debate moderators. Whereas traditionalists often call for journalists onstage to facilitate a discussion that exposes candidates’ differences—a true debate—Raddatz’s questioning on Syria more closely resembled a one-on-one interview.

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The style would arguably cross the line during a contest with two normal candidates, particularly in a town hall-style format. But confusion—purposeful or not—has been a strategic pillar of the Trump campaign like no other candidate before him. That puts greater onus on moderators, the public’s representatives on stage, to coax meaning out of the reality television star’s scattershot words.

Perhaps more importantly, the once omnipresent GOP candidate has in recent months gone into hiding from probing interviewers, instead gravitating toward the likes of Fox & Friends. It is probable that Trump would not face such basic and important questions before election day had Raddatz not stepped in.

This is a broader question for debates in an era of increasingly polarized media. There is less incentive than there once was for candidates to grant interviews to potentially hostile mainstream news organizations. What’s more, this shift toward ideological shelters comes as candidates are more carefully crafting their public images through advanced PR machines that can access audiences rivaling those of traditional news organizations. Trump can speak to millions on Twitter without taking real questions, as he can on the likes of partisan water carriers like Hannity. The same goes for Clinton, though in recent weeks she has been more responsive to news organizations’ questions.

Raddatz’s co-moderator, CNN’s Cooper, was similarly adversarial during the contest. He pressed Trump on his 2005 remarks about groping women—”You bragged that you have sexually assaulted women. Do you understand that?”—and asked Clinton directly if she could unite the country after calling half of Trump’s supporters deplorable. Another line of questioning honed in on Trump’s late-night tweet attack on a former Miss Universe:

COOPER: Mr. Trump, let me follow up with you. In 2008, you wrote in one of your books that the most important characteristic of a good leader is discipline. You said, if a leader doesn’t have it, quote, “he or she won’t be one for very long.” In the days after the first debate, you sent out a series of tweets from 3 a.m. to 5 a.m., including one that told people to check out a sex tape. Is that the discipline of a good leader? TRUMP: No, there wasn’t check out a sex tape. It was just take a look at the person that she built up to be this wonderful Girl Scout who was no Girl Scout. COOPER: You mentioned sex tape. TRUMP: By the way, just so you understand, when she said 3 o’clock in the morning, take a look at Benghazi. She said who is going to answer the call at 3 o’clock in the morning? Guess what? She didn’t answer it, because when Ambassador Stevens… COOPER: The question is, is that the discipline of a good leader?

Trump continued about Benghazi, eventually adding that he is “not un-proud of” his Twitter use. There was no remorse or self-reflection. The exchange seemed to illuminate more than the typical back-and-forths between candidates that often veer toward vacuous talking points.

The dangers of a more assertive moderator are clear: She may focus on what’s new rather than what’s important. Fact-checking is exceedingly difficult in real-time. And it’s likely at least one side will view the performance as a veiled partisan attack. It’s a difficult and thankless job.

But with a candidate who either makes truthiness a hallmark or avoids critical questions wholesale, a more aggressive posture can be a public service. There was much criticism of the Commission on Presidential Debates last month when its executive director came out against moderators truth-squadding in real time. The reality is that, while the debate host prefers more hands-off moderation, the format allows journalists on stage to use whichever tactics they see fit. That flexibility in front of a massive audience is a gift to mainstream media, and Raddatz and Cooper showed how to make good use of it.

Related: Trump’s many, many threats to sue the press since launching his campaign

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David Uberti is a writer in New York. He was previously a media reporter for Gizmodo Media Group and a staff writer for CJR. Follow him on Twitter @DavidUberti.