If one theme emerged from the account presented by prosecutors in the indictment of former President Donald J. Trump that was unsealed on Friday, it was that even after months of relentless news reporting on the case, Mr. Trump’s handling of classified documents was more cavalier — and his efforts to obstruct the government’s attempts to retrieve them more blatant — than was previously known.

On nearly every one of its 49 pages, the indictment revealed a shocking example of Mr. Trump’s indifferent attitude toward some of the country’s most sensitive secrets — and of his persistent willfulness in having his aides and lawyers do his bidding in stymying attempts by the government to get the records back.

Mr. Trump will have an opportunity in court to rebut the account presented by the special counsel Jack Smith. But in the evidence cited in the indictment, there were references to government records being casually kept in a bathroom and on a ballroom stage at Mar-a-Lago, his private club and residence in Florida. There was also a description of a knocked-over stack of boxes lying in a storage room in the basement of the compound, their contents — including a secret intelligence document — spilled on the floor.

At one point, the indictment included an almost cartoonish image. Quoting notes from one of Mr. Trump’s own lawyers, it relates how the former president made a “plucking motion” as if to suggest that the lawyer should go through a folder full of classified materials and “if there’s anything really bad in there, like, you know, pluck it out.”

A classic example of what is known as a “speaking indictment,” the charging document, which was filed on Thursday in Federal District Court in Miami, did far more than merely lay out the seven crimes that Mr. Trump has been accused of — among them, obstruction of justice and the willful retention of national defense records.

The indictment also showcased the bedrock elements of the former president’s personality: his sense of bombast and vengeance, his belief that everything he touches belongs to him and his admiration of people for their underhanded craftiness and gamesmanship with the authorities.

It recounts, for instance, how Mr. Trump had only praise for an unnamed aide to Hillary Clinton who — at least in his narration of the story — helped Ms. Clinton destroy tens of thousands of emails from a private server.

“He did a great job,” the indictment quotes Mr. Trump as telling one of his lawyers.

Why? Because, in Mr. Trump’s account, the aide ensured that Ms. Clinton “didn’t get in any trouble.”

As a baseline matter, the indictment gave the clearest picture yet of the highly sensitive records that Mr. Trump took with him when he left the White House, a startling collection of covert material that included documents about U.S. domestic nuclear programs, potential vulnerabilities to an attack on the homeland and plans for retaliatory strikes on foreign adversaries.

In the bluntest language possible, it explained just how dangerous this was.

“The unauthorized disclosure of these classified documents could put at risk the national security of the United States, foreign relations, the safety of the United States military, and human sources and the continued viability of sensitive intelligence collections methods,” the indictment said.

The indictment did not merely accuse Mr. Trump of holding on to all these files. It also noted that on at least two occasions, he showed — or came close to showing — classified material to others who lacked the proper security clearances to view them.

One of those episodes took place in August or September 2021, when Mr. Trump showed a representative of his political action committee the map of a certain country, commenting that an military operation there “was not going well,” the indictment said.

It went on to describe how Mr. Trump quickly realized that he should not have been displaying the map and told the representative to “not get too close.”

The indictment also related an account of a meeting in July 2021 when Mr. Trump — in a fit of pique at Gen. Mark A. Milley, the chairman of his Joint Chiefs of Staff — brandished a “plan of attack” against Iran to visitors at his golf club in Bedminster, N.J.

To the horror of his aides — one of whom declared, “Now we have a problem” — Mr. Trump admitted that he could have declassified the “highly confidential” document when he was president, but now it was too late because he was out of office.

And yet, as the indictment described in painful detail, he almost seemed unable to control himself.

“This is secret information,” it quoted him as saying. “Look, look at this.”