Two months after Donald Trump’s Inauguration, the White House took a sudden interest in a civil servant named Sahar Nowrouzzadeh. At thirty-four, she was largely unknown outside a small community of national-security specialists. Nowrouzzadeh, born in Trumbull, Connecticut, grew up with no connection to Washington. Her parents had emigrated from Iran, so that her father could finish his training in obstetrics, and they hoped that she would become a doctor or, failing that, an engineer or a lawyer. But on September 11, 2001, Nowrouzzadeh was a freshman at George Washington University, which is close enough to the Pentagon that students could see plumes of smoke climb into the sky. She became interested in global affairs and did internships at the State Department and the National Iranian American Council, a Washington nonprofit. George W. Bush’s Administration appealed for help from Americans familiar with the culture of the Middle East, and, after graduation, Nowrouzzadeh became an analyst in the Department of Defense, using her command of Arabic, Persian, and Dari. (Her brother, a Navy doctor, served in Iraq.) For nearly a decade, Nowrouzzadeh worked mostly on secret programs, winning awards from the Departments of Defense and State, the Office of the Director of National Intelligence, and the F.B.I.

In 2014, she was detailed to the National Security Council, as an Iran specialist, and helped to broker the nuclear deal. One of the most intensely debated questions among American negotiators was how far they could push Iran for concessions, and Nowrouzzadeh proved unusually able to identify, and exploit, subtle divides in Tehran. “She was aggressive,” Norman Roule, the C.I.A.’s highest-ranking Iran specialist at the time, told me. “She worked very hard to follow policymakers’ goals. She could speak Persian. She could understand culture. She is one of the most patriotic people I know.” In 2016, Nowrouzzadeh joined the policy-planning staff of the State Department, a team of experts who advised Secretary of State John Kerry. At times, she advocated a harsher approach to Iran than Kerry was pursuing, but he cherished Nowrouzzadeh’s “unvarnished judgment,” he told me. “I liked someone who relied on facts and could tell me when she disagreed with my interpretation. Give me that any day over a bunch of yes-men.”

On March 14, 2017, Conservative Review, a Web site that opposed the Iran deal, published an article portraying Nowrouzzadeh as a traitorous stooge. The story, titled “Iran Deal Architect Is Running Tehran Policy at the State Dept.,” derided her as a “trusted Obama aide,” whose work “resulted in an agreement that has done enormous damage to the security interests of the United States.” David Wurmser, who had been an adviser to Vice-President Dick Cheney, e-mailed the article to Newt Gingrich, the former Speaker of the House. “I think a cleaning is in order here,” Wurmser wrote. Gingrich forwarded the message to an aide to Secretary of State Rex Tillerson, with the subject line “i thought you should be aware of this.”

As the article circulated inside the Administration, Sean Doocey, a White House aide overseeing personnel, e-mailed colleagues to ask for details of Nowrouzzadeh’s “appointment authority”—the rules by which a federal worker can be hired, moved, or fired. He received a reply from Julia Haller, a former Trump campaign worker, newly appointed to the State Department. Haller wrote that it would be “easy” to remove Nowrouzzadeh from the policy-planning staff. She had “worked on the Iran Deal,” Haller noted, “was born in Iran, and upon my understanding cried when the President won.” Nowrouzzadeh was unaware of these discussions. All she knew was that her experience at work started to change.

Every new President disturbs the disposition of power in Washington. Stars fade. Political appointees arrive, assuming control of a bureaucracy that encompasses 2.8 million civilian employees, across two hundred and fifty agencies—from Forest Service smoke jumpers in Alaska to C.I.A. code-breakers in Virginia. “It’s like taking over two hundred and fifty private corporations at one time,” David Lewis, the chair of the political-science department at Vanderbilt University, told me.

Typically, an incoming President seeks to charm, co-opt, and, when necessary, coerce the federal workforce into executing his vision. But Trump got to Washington by promising to unmake the political ecosystem, eradicating the existing species and populating it anew. This project has gone by various names: Stephen Bannon, the campaign chief, called it the “deconstruction of the administrative state”—the undoing of regulations, pacts, and taxes that he believed constrain American power. In Presidential tweets and on Fox News, the mission is described as a war on the “deep state,” the permanent power élite. Nancy McEldowney, who retired last July after thirty years in the Foreign Service, told me, “In the anatomy of a hostile takeover and occupation, there are textbook elements—you decapitate the leadership, you compartmentalize the power centers, you engender fear and suspicion. They did all those things.”

This idea, more than any other, has defined the Administration, which has greeted the federal government not as a machine that could implement its vision but as a vanquished foe. To control it, Trump would need the right help. “I’m going to surround myself only with the best and most serious people,” he said, during the campaign. “We want top-of-the-line professionals.”

Every President expects devotion. Lyndon Johnson wished for an aide who would “kiss my ass in Macy’s window at high noon and tell me it smells like roses. I want his pecker in my pocket.” But Trump has elevated loyalty to the primary consideration. Since he has no fixed ideology, the White House cannot screen for ideas, so it seeks a more personal form of devotion. Kellyanne Conway, one of his most dedicated attendants, refers reverently to the “October 8th coalition,” the campaign stalwarts who remained at Trump’s side while the world listened to a recording of him boasting about grabbing women by the genitals.

Over time, Trump has rid himself of questioners. He dismissed James Comey, the head of the F.B.I., and then Andrew McCabe, his acting replacement. Gary Cohn, the head of the National Economic Council, resigned early this March, after months of private resistance to Trump’s plan for sweeping trade tariffs. A week later, Tillerson was fired by tweet, receiving notice by phone while he was on the toilet. Nine days after that, the national-security adviser, H. R. McMaster, who had pressed the President to maintain the nuclear deal with Iran, was asked to go, followed quickly by David Shulkin, the head of Veterans Affairs. John Kelly, the once assertive chief of staff, has lost control of access to the Oval Office and of the President’s phone calls; Trump has resumed using his personal cell phone for late-night calls to such confidants as Sean Hannity, of Fox News, who is known in the capital as his “unofficial chief of staff.”

In Washington, where only four per cent of residents voted for Trump, the President hews to a narrow patch of trusted terrain: he rarely ventures beyond his home, his hotel, his golf course, and his plane, taking Air Force One to Mar-a-Lago and to occasional appearances before devoted supporters. He has yet to attend a performance at the Kennedy Center or dine in a restaurant that is not on his own property. As a candidate, Trump rarely went a week without calling a news conference. But in office, as he contends with increasingly intense investigations, he has taken to answering only scattered questions, usually alongside visiting heads of state. He has now gone more than four hundred days without a solo press conference. (Obama held eleven in his first year.)