In the Oval Office, an annoyed President Trump ended an argument he was having with his aides. He reached into a drawer, took out his iPhone and threw it on top of the historic Resolute Desk:
“Do you want me to settle this right now?”
There was no missing Mr. Trump’s threat that day in early 2017, the aides recalled. With a tweet, he could fling a directive to the world, and there was nothing they could do about it.
When Mr. Trump entered office, Twitter was a political tool that had helped get him elected and a digital howitzer that he relished firing. In the years since, he has fully integrated Twitter into the very fabric of his administration, reshaping the nature of the presidency and presidential power.
After Turkey invaded northern Syria this past month, he crafted his response not only in White House meetings but also in a series of contradictory tweets. This summer, he announced increased tariffs on $300 billion worth of Chinese goods, using a tweet to deepen tensions between the two countries. And in March, Mr. Trump cast aside more than 50 years of American policy, tweeting his recognition of Israel’s sovereignty in the Golan Heights. He openly delighted in the reaction he provoked.
“Boom. I press it,” Mr. Trump recalled months later at a White House conference attended by conservative social media personalities, “and, within two seconds, ‘We have breaking news.’”
Early on, top aides wanted to restrain the president’s Twitter habit, even considering asking the company to impose a 15-minute delay on Mr. Trump’s messages. But 11,390 presidential tweets later, many administration officials and lawmakers embrace his Twitter obsession, flocking to his social media chief with suggestions. Policy meetings are hijacked when Mr. Trump gets an idea for a tweet, drawing in cabinet members and others for wordsmithing. And as a president often at war with his own bureaucracy, he deploys Twitter to break through logjams, overrule or humiliate recalcitrant advisers and pre-empt his staff.
“He needs to tweet like we need to eat,” Kellyanne Conway, his White House counselor, said in an interview.
In a presidency unlike any other, where Mr. Trump wakes to Twitter, goes to bed with it and is comforted by how much it revolves around him, the person he most often singled out for praise was himself — more than 2,000 times, according to an analysis by The New York Times.