At the entrance of the Oval Office, where the president and his visitors can see it every day, hangs the mug shot taken of a glowering Donald J. Trump after being arrested and charged with racketeering to overthrow an election.

A couple of hundred feet away, in the grand foyer of the White House state floor where the official portraits of past presidents in solemn poses are on display, hangs a painting of a defiant Mr. Trump, blood splattered on his face by would-be assassin’s bullet, angrily pumping his fist and shouting, “Fight! Fight!”

These icons of Mr. Trump’s journey back to power loom large as he completes the first 100 days of his second presidency. There is a reason he has placed these images in positions of prominence. They reflect the crucibles of a man who escaped existential threats of prison and death in his quest for vindication and vengeance. They fuel his self-authored narrative as a man of destiny, saved by God to save America.

Mr. Trump has done more to change the trajectory of the country in three months than any president since Franklin D. Roosevelt introduced the notion of a first-100-days presidential yardstick. But where Roosevelt used his early weeks to build a new edifice, Mr. Trump has used his to tear it down.

“He is very laser focused on what he wants to accomplish,” said Robert Jeffress, the Dallas evangelical pastor, who joined the president at an Easter dinner at the White House this month. The trials and tribulations of the past few years, including the 2024 assassination attempt in Butler, Pa., took time to process, Mr. Jeffress added. “But I think he came to the conclusion — the right conclusion — that God has a purpose for him.”

It has been an action-packed 100-day sprint of remarkable grandiosity and vindictiveness. In his war on the so-called deep state that he blames in part for his ordeals of the past few years, Mr. Trump has ripped through the federal government with cyclone force, dismantling government agencies, eliminating diversity programs, gutting climate change initiatives, firing tens of thousands of workers, slashing spending on foreign aid and scientific research, installing partisan warriors at the Justice Department and F.B.I. and purging the top uniformed military leadership.

He has cracked down on immigration, bringing crossings at the border to historic lows even as his agents have defied courts in deporting migrants who were in the country both illegally and legally. He has put pressure on law firms, universities, news outlets and sports leagues to change policies to suit his wishes. Adopting a new “manifest destiny,” he has coveted territory in Greenland, Canada, the Panama Canal and even war-torn Gaza.

He has gone after his critics much as he vowed to do, ordering Justice Department investigations of specific adversaries by name, stripping security details from former officials facing death threats, firing government officials who crossed him or even just went to the wedding of someone who had crossed him.

No issue appears too small for him to address if it piques his interest, including plastic straws, shower pressure and the lineup at the Kennedy Center. At the same time, he and his family have profited significantly off the presidency through business ventures, cryptocurrency and a promotional documentary about Melania Trump.

But some of the president’s most high-profile initiatives either have yet to bear fruit, early as it is, or have generated enormous tumult.

“F.D.R.’s accomplishments were enduring,” said H.W. Brands, a Roosevelt biographer at the University of Texas at Austin. “The Supreme Court overturned some but they were revised and reinstated. Most are with us still. Trump’s accomplishments, so far, can be undone by mere strokes of the pens of his successors.”

“These first hundred days have been historic, not because of how much of his agenda he has achieved, but because of how much damage he has done to democratic institutions and state capacity in his effort to wield an unprecedented amount of executive power,” said Nicole Hemmer, director of the Carolyn T. and Robert M. Rogers Center for the American Presidency at Vanderbilt University.

But while Mr. Trump claims a mandate from both God and voters, the voters, at least, are not so sure. He finishes his first 100 days with less public support than any president in the history of polling at this stage. Just 42 percent of voters approved of his performance in a survey by The New York Times and Siena College that found Americans using words like “chaotic” and “scary” to describe his tenure so far.

Mr. Trump has never been a popular president, even though he plays one on television. Although he won the Electoral College in 2016, he lost the popular vote. While he edged out Vice President Kamala Harris by 1.5 percentage points in 2024, he fell just short of 50 percent. He has never had the approval of a majority of voters in any Gallup poll in his first or second terms, unlike any president going back to Roosevelt.

He looks up most days and sees that mug shot and maybe passes that painting with the blood on his face and he knows what could have been. By all accounts, for good or ill, he has changed the country in just 100 days. Under the Constitution, he has 1,361 more to go.