The Mysteries of Mar-a-Lago

Donald J. Trump loves to attack the “deep state” — the imaginary cabal of soldiers, spies and secret agents seeking to destroy him from within the government. In the last year of his presidency, he aimed to slay that mythical beast.

He placed loyalists in powerful posts atop the intelligence community and the Pentagon, seeking to rifle through their top-secret files in search of evidence that the “deep state” spied on his 2016 campaign, then framed him for his dealings with Russia and Ukraine, acts for which he was investigated and impeached.

Now the tables have turned. Last week, the Federal Bureau of Investigation searched the ex-president’s own secret files, igniting a bitter legal battle and a political attack by Mr. Trump and his allies against the F.B.I. The judge who signed the search warrant has ordered the Justice Department to propose which parts of the F.B.I. affidavit justifying the search and seizure of the sensitive files may be unsealed, if and when they are. The government has made clear that Mr. Trump had no right to possess these records.

The F.B.I. can make a strong case against Mr. Trump — thanks to a law created because of the crimes of Richard Nixon.

On May 3, 1973, days after the F.B.I. searched the White House to seize presidential files pertaining to Watergate, Nixon sat down with Richard Kleindienst, who had just resigned as attorney general. The Oval Office tapes were rolling.

“They’re my files,” Nixon wailed. “They belong to me.”

Under investigation by the Department of Justice and Congress, Nixon kept concealing, altering and destroying records. He fought the government for possession of his tapes for 20 years until his death.

After Watergate, Congress had to confront the idea that presidential records could be criminal evidence. It sought to refute Nixon’s edict: “When the president does it, that means it is not illegal,” a principle dear to Mr. Trump’s heart. Congress passed a law, the Presidential Records Act, to preserve the integrity of Nixon’s White House documents — which by tradition did, in fact, belong to him — and until now, all who came after him have obeyed it.

The law made clear that presidential files ultimately belong to the people. They automatically become the property of the National Archives when the chief executive leaves office. Twelve years later, they become public records, available through the archives and presidential libraries. An ex-president is responsible for the chain of custody that the law commands.

Last year, the National Archives asked the Trump White House deputy counsel, Patrick F. Philbin, to secure the release of all the files the ex-president was hoarding. He failed, so the Archives contacted the Justice Department, which called in the F.B.I. But Mr. Trump has continued to resist entreaties from his advisers to return the classified materials to the Archives.

“It’s not theirs, it’s mine,” Mr. Trump told them.

The Mar-a-Lago papers may well determine if Mr. Trump has a political future. That depends, in part, on the solution to several mysteries. What is in those files? Where did they come from? Whose fingerprints are on them? And who shows up on the surveillance tapes subpoenaed from the Trump mansion, which will show who went in and out of the rooms where they were hidden?

If and when the affidavit is unsealed, which could happen as soon as next Thursday, we may get answers to some of these questions. But Kash Patel, a former National Security Council staff member whom Mr. Trump appointed as a legal liaison to the National Archives on June 19, has suggested that the documents relate “not just to Russiagate, but to national security matters, to the Ukraine impeachment.”

Mr. Patel, who sports a large lapel pin reading “K$H,” was one of the Trump appointees who led the attempt to uncover the secrets of the “deep state” that consumed the president during his last year in power. He served, by turns, as the right hand to the acting director of national intelligence and the acting secretary of defense. And in his desperate final weeks in office, Mr. Trump came close to making Mr. Patel acting director of the Central Intelligence Agency. Faced with the wrath of the actual director, Gina Haspel, the president backed down at the last minute.

But Mr. Patel remained in the ex-president’s orbit as the confrontation over the Mar-a-Lago cache slowly escalated this spring. In June, when he became an official National Archives representative, a Trump spokeswoman emphasized that Mr. Patel was working to disclose “documents that reveal a clear conspiracy to unlawfully spy on candidate and then President Donald J. Trump” — in other words, the same sorts of documents he seems to have been seeking to uncover at the highest levels of American intelligence two years ago, at Mr. Trump’s command. (Mr. Patel did not return an email seeking comment.)

We may not know what these documents reveal for some time; whenever the F.B.I. affidavit justifying the search is unsealed, it’s likely to be heavily redacted. But given eyewitness accounts of Mr. Trump’s tumultuous last days in the White House, they may well be a Pandora’s box of secrets scooped out of the Oval Office and perhaps hoarded for the political or personal benefit of the ex-president.

What we do know is that this case is not a paper chase. And it’s more than a legal effort to preserve history for future generations. It’s a counterintelligence matter involving espionage laws intended to protect the nation’s secrets and detect spies. And Mar-a-Lago, according to intelligence veterans, has long been a target for foreign spies, as has Mr. Trump.

Such investigations can take a generation to develop. It took the F.B.I. nearly two decades to catch one of its own agents who was spying for Moscow. Sometimes they disappear into thin air. But it may be that a storm is brewing off the coast at Palm Beach.

Whatever the outcome, someday we’ll get a glimpse at what Mr. Trump has been hiding in his gilded palace. Presidents have few secrets that time will not reveal.

Tim Weiner (@Folly_and_Glory) is a former national security correspondent for The New York Times and the author of six books, most recently, “The Folly and the Glory.” He is currently working on a history of the C.I.A. in the 21st century.

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