Joe Kent, the newly confirmed director of the National Counterterrorism Center, once complained that federal agencies responding to the Jan. 6 attack on the U.S. Capitol were promoting “a narrative that labels all of us terrorists or insurrectionists just for questioning things.” It was September 2021, and Kent was an Iraq war veteran and candidate for Congress, speaking at the “Justice for J6” rally at the U.S. Capitol. Kent claimed without evidence that the Jan. 6 defendants were “political prisoners” who had been “denied due process” — thereby pioneering a false claim Donald Trump would use in his 2024 presidential...