Donald Trump is obsessed with keeping secrets and catching those who reveal them. To understand this week’s news that he wants former FBI director James B. Comey locked up for leaking classified information, let’s travel back to a more innocent time in our nation’s history: the fifth full week of the Trump administration.

“The FBI is totally unable to stop the national security ‘leakers’ that have permeated our government for a long time,” President Trump tweeted on Feb. 24, 2017. “They can’t even find the leakers within the FBI itself.” He then demanded, with what is now characteristic all-caps emphasis: “FIND NOW.”

The administration went on the hunt. Trump’s Justice Department brought 120 leak cases to prosecutors in 2017, and 88 in 2018, according to the Project on Government Secrecy at the Federation of American Scientists. The annual average in the Obama administration was 39, then a record number. Ten cases came to trial in Barack Obama’s eight years in office; six during Trump’s first two years.

Does this mean there is more leaking under Trump? Sure. Why? I suspect it’s because there’s a whole lot more wrongdoing. In the end, what the government calls leaks are, 9 times out of 10, what reporters call an essential part of reporting. Governments conceal secrets with a bodyguard of lies. Without reporters gathering classified information, we would know little or nothing about the CIA torturing prisoners in black sites, the National Security Agency’s warrantless wiretapping of Americans, or, for that matter, the depth and nature of the Russian attacks on our elections. A democracy doesn’t run on government news releases.

Attorney General William P. Barr has his bloodhounds after Comey for a leak concerning the existence of the FBI’s counterintelligence investigation — which hasn’t ended, as far as anyone knows — into Russia’s attack on the 2016 election and Team Trump’s repeated contacts with Team Putin. Trump fired Comey to try to stop the investigation, and he has made clear for nearly three years his desire to see Comey indicted, convicted and behind bars, most recently in a tweet three days before the House impeached him: “What are the consequences for his unlawful conduct? Could it be years in jail?”

It has almost always been the leakers who go to jail, but Barr, at his confirmation hearings a year ago, declared himself perfectly willing to imprison reporters if necessary. As the subject of a few leak investigations myself during the Clinton administration, when I covered the CIA for the New York Times, I found them to be the legal equivalent of a snipe hunt, leading nowhere. But nowadays they have a decidedly chilling effect on national-security reporters and, more so, their sources.

Any criminal referral for a leak of classified information has to pass an 11-point test. The key questions are: Was the story true? Was the information in it truly a secret? Does it really have an impact on national security?

One dilemma for the CIA, in my day, was that by filing a crimes report saying classified information had leaked, it was confirming that the information was true. For my part, if I had a secret in hand, I would always try to talk to the highest-level CIA officials I could consult, up to and including the director, to make sure it wasn’t information that could do real damage.

Trump has played the role of leaker-in-chief, disclosing secrets of state to everyone from the Russian foreign minister to rich donors at Mar-a-Lago, but the most damaging leaks of classified information by far are sprung by hostile intelligence services. To Trump, though, the real enemies of the people aren’t Russian spies, but reporters — and people like Comey, the conspiratorial saboteurs who run the “deep state.”

The newly disclosed criminal investigation of Comey is a particularly nasty case that draws together Trump’s appetite for vengeance, an especially odoriferous piece of Russian disinformation and Comey’s decision to deep-six the FBI investigation into Hillary Clinton’s emails as the 2016 election approached. It’s like a greatest-hits album of the past three years.

A refresher: Comey testified to Congress in May 2017 about the counterintelligence investigation into Russian interference in the election. Trump ousted Comey and bragged to the Russian ambassador and foreign minister that he’d freed himself from “great pressure.” But the heat was on again within the week, when special counsel Robert S. Mueller III took over the case.

On Sept. 1 of that year, Trump, through his counsel John Dowd, sent a smoking-hot email to Mueller’s Justice Department overseer, Rod J. Rosenstein, denouncing “Mr. Comey’s plainly deliberate, unlawful conduct and false Congressional testimony” and calling for “a full Federal Grand Jury investigation into the obviously corrupt closing of the email investigation of Secretary Clinton including the highly irregular and bizarre conduct of Mr. Comey.”

The key to all this is a document the FBI received during the 2016 election season. As The Washington Post reported in May 2017, it was a Russian intelligence report, and it asserted that the Clinton campaign and the Obama Justice Department had a deal to soft-pedal the inquiry into whether she intentionally revealed classified information through her private email server. But it was a fake — one strand in the web of Russian disinformation, created with the intent of throwing the election into chaos. Its falsity factored into Comey’s decision to close the case.

Take note: The leak the president continues to want prosecuted was the disclosure of the fact that the document was a fraud. Here, as in so much else, including his mad pursuit of dirt on former vice president Joe Biden, Trump chose to believe Russia disinformation. The connoisseur of conspiracy theories believes the Russian lie that Ukraine was to blame for the 2016 election hack, and that has led him down the road to impeachment.

To peer into the depths of Trump’s desire to nail Comey for a three-and-a-half-year-old leak is to get a glimpse into what awaits if the Senate acquits Trump and he is reelected by the citizenry. His threats to prosecute his political opponents for lèse-majesté — the crime of criticizing the monarch, tantamount to treason — are sure to advance beyond tweets after he is sworn in for a second term. Leakers and whistleblowers — and reporters — beware.