If Mr. Trump’s slap-and-tickle relationship with reporters had a model back then, people close to him say, it was the gregarious, unavoidable-for-comment style of Edward I. Koch, the three-term New York mayor. But his mood in Washington has turned darker, and over the last week he has executed, alongside Mr. Bannon and Mr. Spicer, what amounts to the most sustained White House campaign against the news media since Richard M. Nixon’s second term.

“It’s like Nixonian times again,” said George Rush, a veteran New York gossip columnist who has covered Mr. Trump for decades. “I just thought he would have a thicker skin.”

Linda Stasi, who chronicled Mr. Trump’s up-and-down marriage to Marla Maples in the 1990s for two New York papers, said she could have predicted the presidential agita. “He would plant stories and he would get mad if they didn’t come out exactly as he wanted,” she recalled of earlier dealings with Mr. Trump. “It never occurred to him that he couldn’t control everything.”

Now, Ms. Stasi said, “he is shocked that he is not in control of the press.”

Attacking the news media, which has an abysmal approval rating among Republican voters, is sound politics in the short term. But Mr. Trump’s fury is less strategic than heartfelt. He watches cable TV at night and exhorts aides like Mr. Spicer and his policy adviser Stephen Miller to be tougher, according to White House aides.

His anger is compounded by his belief that he should still be able to plant and steer stories. That was a lot easier to do when he was running a close-knit real estate and branding business with an aggressive legal team that demanded that nearly everyone in his orbit sign nondisclosure agreements.

For the first time in his life, Mr. Trump is on the public payroll and subject to a tangle of laws and rules no businessman — especially one accustomed to overseeing every aspect of a relatively small family business — would tolerate.