The President's personal leaker https://www.nytimes.com/2020/10/20/opinion/john-ratcliffe-trump.html?smid=tw-share

There have been several candidates for worst intel officer who debased the profession and damaged the system itself. Michael Flynn’s poor judgment got him fired from both of his senior jobs before he could do too much damage but his legacy will nonetheless be lasting. /2

Flynn injected domestic politics into national security matters, enabled Trump’s twisted view that our intel, law enforcement and national security professionals are part of a “deep state,” willingly engaged in a Kremlin propaganda stunt, and lied to the FBI about his contacts./3

The former three-star General’s embrace of angry, loony and fringe groups suggests he has more fidelity to his QAnon oath than to his Constitutional one. Second, Douglas Feith cherry-picked intelligence for the Bush Administration to help make a case for war. /4

Ratcliffe’s predecessor at the DNI Rick Grinnell treated the intelligence community as if it was Trump’s personal opposition research arm. Luckily, he didn’t last more than a few months as both Democrats and Republicans realized he was a disaster. /5

Prior to the Trump Administration, intelligence historians would cite James Jesus Angleton, the twenty-year Counterintelligence Chief at the CIA from the 50s to the 70s, whose paranoia and belief in gargantuan Soviet plots twisted the CIA inside out. /6

I discuss MacArthur's intelligence chief Willoughby as a particularly heinous officer. I have to say however, Ratcliffe is making a strong claim at being the most damaging of all.