Republicans on the committee were generally unbowed by Hill’s admonition, as they continued to press her and Holmes on the discredited allegation that Ukraine interfered on Clinton’s behalf to the same extent that Russia interfered on Trump’s. They also asked her to square her version of events surrounding the alleged quid pro quo with Ukraine with the recollections offered by earlier witnesses. That led to a dramatic exchange between Hill and Steve Castor, the Republican committee counsel.

After Castor asked Hill about what she had described as a “blowup” between her and Sondland in June over a lack of coordination on Ukraine policy, Hill took the opportunity to say that, in retrospect, she had been angry at Sondland without proper cause. In the process, she ended up explaining the entire crux of the Ukraine scandal—how over a period of months, a political priority of Trump’s ended up converging with and then overtaking the nation’s official policy of support for an adversary of Russia. Hill said that while she had confronted Sondland because she had perceived that he was keeping her and others on the NSC out of the loop, she realized only later that the two were on different missions.

“He was absolutely right—that he wasn’t coordinating with us, because we weren’t doing the same thing that he was doing,” Hill testified. “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.”

She recalled that she told the ambassador, “I think this is all going to blow up.” She added: “And here we are.”

As the hearing proceeded, Republican lawmakers asked fewer questions of Hill and Holmes and used their allotted time to instead make speeches. At one point, after three GOP members in a row had ranted at Hill without allowing her to respond, she asked for the opportunity to speak. She spoke up in defense of immigrants and elections free of interference from any country, voicing the hope that the 2020 election would offer Americans a clear opportunity to make a “monumental” choice about their future.

By the time she spoke, however, she noted that two of the three Republicans who had criticized her had left the room.

As compelling as her entire account turned out to be, it is Hill’s blunt warning to Republicans at the outset that might break through the din of a process that has, like so many previous investigations, become ensnared in partisan bickering. Democrats have been trying for years to call out both Trump and his GOP allies for, wittingly or not, falling prey to Russian propaganda campaigns. None of those attempts, however, has resonated as loudly as the siren sounded this morning—not from the committee dais but from the witness table, and sung not by a Democrat but by a policy expert who worked for the president himself.

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