Fiona Hill, the former National Security Council official who testified at the impeachment hearings on Thursday, was born in Bishop Auckland, a hardscrabble former coal town in County Durham, in the northeast of England. Her father was a miner; her mother was a nurse. As she noted in her testimony before the House Intelligence Committee, her modest roots and working-class accent would have been a career handicap in the Britain she grew up in, but in the late nineteen-eighties she escaped. After attending the University of St. Andrews, in Scotland, she applied for a graduate scholarship to Harvard and was called for an interview. “I was so nervous, I walked into a broom closet by accident,” she later recalled.

Hill, who appeared at the Longworth House Office Building, on Thursday morning, didn’t appear to be nervous at all, and why should she have been? At Harvard, she earned a Ph.D. in Russian history. In 2002, she became an American citizen. For many years, she has been a senior fellow at the Brookings Institution, in Washington. From 2006 to 2009, she served as the senior expert on Russia and Eurasia at the National Intelligence Council, an internal think tank for U.S. intelligence agencies. In 2013, she and Clifford G. Gaddy, an economist at Brookings, published “Mr. Putin: Operative in the Kremlin,” which a reviewer at Foreign Affairs described as the single book about Putin that is most useful to policymakers. In 2017, Hill was named the senior director for European and Russian affairs at the National Security Council, where she served as a deputy to H. R. McMaster and John Bolton.

“I can say with confidence that this country has offered for me opportunities I would never have had in England,” Hill said in recounting her modest upbringing. Then she got down to business, delivering a short lecture to certain unnamed members of the committee about the realities of Russian interference in the 2016 election. “Some of you on this committee appear to believe that Russia and its security services did not conduct a campaign against our country—and that perhaps, somehow, for some reason, Ukraine did,” Hill said. “This is a fictional narrative that has been perpetrated and propagated by the Russian security services themselves. The unfortunate truth is that Russia was the foreign power that systematically attacked our democratic institutions in 2016.”

Hill was just getting started. Reading in a firm voice from her opening statement, she went on to say that Russia’s goal was to weaken the United States, partly by sowing internal dissent. “President Putin and the Russian security services operate like a super PAC,” she said. “They deploy millions of dollars to weaponize our own political opposition research and false narratives. When we are consumed by partisan rancor, we cannot combat these external forces as they seek to divide us against each other, degrade our institutions, and destroy the faith of the American people in our democracy.” Hill also repeated the warning that Robert Mueller delivered during his testimony to Congress, in July, and she coupled that warning with another about the useful idiots inside the United States who, deliberately or not, serve to further Russia’s goals. “Russia’s security services and their proxies have geared up to repeat their interference in the 2020 election,” she said. “We are running out of time to stop them. In the course of this investigation, I would ask that you please not promote politically driven falsehoods that so clearly advance Russian interests.”

It isn’t every day that a former senior official in the Trump White House effectively accuses congressional Republicans of promoting “false narratives” in a manner that benefits the Kremlin. Even before Hill started talking, Devin Nunes, the ranking Republican on the committee, had sought to counter her assertions. During his opening statement, he lifted up a lengthy report into Russian meddling that he and his Republicans colleagues put out in 2018. Remarkably, however, Nunes then confirmed Hill’s charge by saying it was “entirely possible for two separate nations”—e.g., Russia and Ukraine—“to engage in election meddling at the same time, and Republicans believe we should take meddling seriously by all foreign countries.”

During the question-and-answer session, Hill calmly confirmed much of what we already know about the Ukraine story, including the circumstances in which her boss, Bolton, said to her, on July 10th, “You tell Eisenberg”—John Eisenberg, the N.S.C.’s chief counsel—“that I am not part of whatever drug deal Mulvaney”—Mick Mulvaney, the acting White House chief of staff—“and Sondland”—Gordon Sondland, the Ambassador to the European Union—“are cooking up.” She also recalled how Sondland had said that he had an agreement with Mulvaney; in return for Volodymyr Zelensky, the recently elected President of Ukraine, opening investigations into the 2016 election and Burisma, the energy company that employed Hunter Biden, President Trump would agree to a face-to-face meeting with him.

Under questioning from Steve Castor, the Republican staff counsel, Hill recalled how, before she left the White House, on July 19th, she had “a couple of testy encounters” with Sondland, because he refused to coördinate in the usual interagency processes and insisted he was working directly for the President. Having watched Sondland testify to the committee about his contacts with Trump and other senior members of the Administration, she said, she now felt very differently about Sondland’s attitude and his behavior. “He was absolutely right,” she said. “Because he was being involved in a domestic political errand and we were being involved in national-security foreign policy, and those two things had just diverged. So he was correct. I had not put my finger on that at the moment, but I was irritated with him and angry with him that he wasn’t fully coördinating. And I did say to him, ‘Ambassador Sondland, Gordon, I think this is also going to blow up.’ And here we are.”

That was a brilliant synopsis of the entire Ukraine caper, and it showed why Adam Schiff, the Intelligence Committee chairman, and the Democrats chose to make Hill one of the two final witnesses, at least in this round of hearings. Her testimony will also be remembered for her manifest smarts, her directness—a trait of the region where she grew up—her steely self-confidence, and the moral earnestness she displayed. She said she felt a “duty” to testify despite the fact that it had led to her being subjected to a harassment campaign. When two Republican congressmen—Mike Turner and John Ratcliffe—left the hearing room immediately after making some dismissive comments about her testimony, she didn’t hesitate to rebuke them.

Read More Susan B. Glasser on Ambassador Sondland’s revenge.

By midafternoon, Hill was being saluted online as a feminist hero. Jackie Speier, a California Democrat and a member of the Intelligence Committee, got her to confirm that, when Hill was an eleven-year-old schoolgirl, a fellow-pupil had set her pigtails on fire during a school test, and, after extinguishing the flames with her hands, she had completed the test. The incident had negative consequences, Hill recounted dryly. Because of the damage to her hair, her mother forced her to get a bowl cut, and “I looked like Richard III.”

History buffs will recall that the fifteenth-century king was killed fighting the rebellious forces of Henry Tudor during the War of the Roses, making him the last English monarch to die in battle. It would be a stretch to compare Hill to a Plantagenet warrior, but perhaps not a completely outrageous one. “We can’t let this stand,” she said at one point. “And I don’t think anyone here thinks we can let this stand.” She was referring specifically to the outrageous smear attacks that President Trump’s personal lawyer, Rudy Giuliani, and others carried out on Marie Yovanovitch, the former U.S. Ambassador to Ukraine. But Hill’s entire testimony was making a broader point about the need to defend the stated values of her adopted country, and the threats it faces—internal as well as external. The message couldn’t have come through more clearly.