We already knew that the FBI worried about Trump thinking they were blackmailing him. Comey testified to that months ago.

Senior FBI officials were concerned then director James Comey would appear to be blackmailing then President-elect Trump – using tactics notoriously associated with J.Edgar Hoover – when he attended a fateful Jan. 6, 2017, meeting at which he informed the real estate magnate about allegations he had consorted with prostitutes in Moscow, according to Jim Baker, the bureau’s chief counsel at the time.

“We were quite worried about the Hoover analogies, and we were determined not to have such a disaster happen on our watch,” said Jim Baker, then the FBI’s top lawyer in an interview with the Yahoo News podcast Skullduggery. But he and Comey determined the bureau had an obligation to tell Trump of the uncorroborated allegations because “the press has it; it’s about to come out. You should be alerted to that fact.”
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“It was pretty alarming,” Baker said about intelligence the bureau had about possible links between the Trump campaign and various Russian actors. “The thought that somehow somebody in either one of the campaigns might have had some connection to that or some awareness of it that they didn't inform the FBI about was … quite concerning and disorienting.”

The issue was so sensitive that when Comey was preparing to brief Trump after the election, Baker and the director were directly at odds about how to handle the matter. The meeting was crucial: It was the moment that the U.S. intelligence chief — including Comey — were to brief Trump, then the president-elect, about their findings about the Russian government’s efforts to interfere in the election that Trump had just won.

Baker strongly urged Comey not to go through with his plans to reassure Trump by telling him he was not under investigation by the FBI. “I didn't think it was accurate to say that he wasn't under investigation,” said Baker.

As Baker saw it, Trump was clearly a “subject” of the investigation because, as head of his own campaign, he was among those whose activities were being examined by the FBI.

But Comey thought explaining that distinction to the president-elect would have been “too confusing.” It would have been “hard to understand, be misinterpreted and he just didn't think it was the right thing to do,” Baker said about Comey’s view about what to say.

In the end, Comey told Trump he was not under investigation—a comment that came back to haunt Comey when he later refused to say the same thing publicly, a key factor that led to Trump’s decision to fire him.

COMEY: I didn't use the term counterintelligence. I was briefing him about salacious and unverified material. It was in a context of that that he had a strong and defensive reaction about that not being true. My reading of it was it was important for me to assure him we were not person investigating him.

So the context then was actually narrower, focused on what I just talked to him about. It was very important because it was, first, true, and second, I was worried very much about being in kind of a J. Edgar Hoover-type situation.

I didn't want him thinking I was briefing him on this to sort of hang it over him in some way. I was briefing him on it because, because we had been told by the media it was about to launch. We didn't want to be keeping that from him.

He needed to know this was being said. I was very keen not to leave him with an impression that the bureau was trying to do something to him. So that's the context in which I said, sir, we're not personally investigating you.