One more stop on a busy presidential day: the Super Bowl.

Of greater significance, he announced that, starting Monday, he would impose a 25 percent tariff on all foreign steel and aluminum imports into the United States. He also said he still intended to move forward with taking over the Gaza Strip, which he described as a “big real estate site” that the United States was “going to own.”

And he defended his first three weeks in office, which have caused massive strife across the country and the globe.

That was all before the game started.

Mr. Trump was met with cheers and a mix of boos as he arrived at the Superdome for the game, between the Kansas City Chiefs and the Philadelphia Eagles. Among his entourage were his son Eric Trump and Eric’s wife, Lara Trump; his daughter Ivanka Trump; and several Republican leaders.

Also at the game is the former first lady Jill Biden, an avid Eagles fan, and her grandson, Beau Biden’s son Hunter. Former President Joseph R. Biden Jr., whose security clearance Mr. Trump revoked on Friday, was not in attendance.

Mr. Trump and his courtiers were escorted to a suite at the Superdome, where he was seen standing for the national anthem and saluting.

In excerpts from an interview that aired earlier Sunday, Mr. Trump told the Fox News anchor Bret Baier that he had chosen to attend the Super Bowl because he thought it would be a “good thing” for the spirit of the country, which he said has “taken on a whole new life.”

Asked who he thought would win the game, Mr. Trump praised the quarterbacks of both teams, but he ultimately said he’d go with Kansas City based on the record of its star quarterback, Patrick Mahomes — who, he added, had “a phenomenal wife” (Brittany Mahomes) who happened to be a “Trump fan.”

“It’s going to be just a great game,” Mr. Trump said.

In the description on YouTube, the video’s creators’ list what they might do with $40 million, including purchasing “life-saving HIV treatment from American pharmaceutical companies to keep 1,060,000 million people alive for one year” and buying “66,000 metric tons of crops from American farmers” to send overseas “to feed 8 million people on the brink of famine.”

“There won’t be anybody there,” Trump added. “Hamas won’t be there. We’ll be building through other of the very rich countries in the Middle East, they’ll be building some beautiful sites for the people, the Palestinians, to live in.”

It says the men are being held in the same Immigration and Customs Enforcement facility, the Otero County Processing Center, where previous groups of men flown to Guantánamo in recent days had apparently been held. They recognized the faces of some of those detainees from government photographs provided to the news media, it said.

The filing also said the men had heard rumors that more such transfers were coming, and said that they “fit the profile of those the administration has prioritized for detention in Guantánamo, i.e. Venezuelan men detained in the El Paso area with (false) charges of connections with the Tren de Aragua gang.”

President Trump issued a directive to the Homeland Security and Defense Departments on Jan. 29, ordering them to prepare to expand a migrant operations center to “provide additional detention space for high-priority criminal aliens unlawfully present in the United States.” The military also sent troops to help expand a tent city on one side of the base at Guantánamo Bay.

Since then, five military flights have taken undocumented immigrants there. So far, however, the men have been housed in an empty wing of the wartime prison complex erected by the Bush administration to hold terrorism suspects after the attacks of Sept. 11, 2001.

The legal challenge brought on behalf of the men is relatively modest. It does not seek to block the administration from sending any more migrants to Guantánamo in general — only the three specific detainees. And the filing acknowledges that a lawyer for the government told them that none of the three “are being moved” to the naval base, though it argues that this could change.

While the U.S. government has taken migrants intercepted at sea to Guantánamo to be processed, it is different to take people who were already on American soil — and therefore covered by the Constitution, even if they were in the United States unlawfully — to the Navy base on Cuban soil to be held in immigration detention.

The Supreme Court has ruled that the government may hold Qaeda detainees at Guantánamo under a law passed by Congress that authorizes the use of military force against the perpetrators of the Sept. 11 attacks. It is not clear what legal authority the Trump administration has to take migrants there and hold them in continued immigration detention.

The filing came as part of an existing lawsuit brought by the men that has been filed by the Center for Constitutional Rights, the New Mexico chapter of the American Civil Liberties Union of New Mexico, and the Las Americas Immigrant Advisory Center.

The men are subject to removal orders after their asylum requests were rejected. But they have been jammed up because of the breakdown in relations between the U.S. government and that of their native Venezuela under President Nicolas Maduro.

That lawsuit argues that the men cannot be held in perpetual detention and so must be freed. The new filing asks the court to block any attempt by the government to send them to Guantánamo, arguing that any such transfer would make it difficult for them to continue to communicate with their lawyers and could open the door to the government’s arguing that the court no longer has jurisdiction.

Carol Rosenberg contributed reporting from Miami.

“Any steel coming into the United States is going to have a 25 percent tariff,” Mr. Trump said. “Aluminum, too.”

Mr. Trump’s decision to tax foreign metals and impose reciprocal tariffs comes in the wake of several other trade threats he has made since winning the White House.

Since taking office, Mr. Trump has imposed an additional 10 percent tariff on all products from China, and came within hours of imposing sweeping tariffs on Canada and Mexico that would have brought U.S. tariff rates to a level not seen since the 1940s.

Mr. Trump has also said in recent days that he planned to impose tariffs on Europe, Taiwan and other governments, as well as on a variety of critical industries like copper, steel, aluminum, pharmaceuticals and semiconductors.

The decision to impose tariffs on metals would affect some of America’s biggest trading partners and allies.

The largest supplier of steel to the United States in 2024 was Canada, followed by Brazil, Mexico, South Korea and Vietnam, according to the American Iron and Steel Institute. Canada is also a major supplier of aluminum to the United States, followed distantly by the United Arab Emirates, Russia and China.

Mr. Trump’s decision to impose tariffs on metals is not new. In his first term, the president levied tariffs on foreign steel and aluminum globally, angering allies like Mexico, Canada and the European Union. He ultimately rolled back some of those barriers on Canada and Mexico when they signed a revised trade agreement with the United States.

The Biden administration later reached agreements with the European Union, the United Kingdom and Japan to roll back some of their trade restrictions. A handful of other countries also negotiated quotas or other arrangements, but for most countries the steel and aluminum tariffs remain in place, said Chad Bown, a senior fellow at the Peterson Institute for International Economics. It’s not clear if the new tariffs would be added to the old ones.

Both of Mr. Trump’s new tariff proposals would broaden his trade fight to many different countries, setting off trade spats that could encourage other countries to retaliate with their own tariffs on American goods.

Mr. Trump has already rocked diplomatic and economic relationships over the past week with almost-daily tariff threats.

The reciprocal tariffs the president has proposed would raise the levies the United States charges on certain imports to match what other countries charge on American products when those goods come across their borders. They could be used by the president as a lever to seek further concessions in negotiations. But they would also violate U.S. commitments to the World Trade Organization.

The president said his reciprocal tariffs would be announced on Tuesday or Wednesday at a news conference, and the tariffs would go into effect “almost immediately” on every country.

“Very simply, if they charge us, we charge them,” he said.

Trump signed the proclamation on his way to New Orleans. In rare audio from Air Force One shared with reporters, a member of the flight crew announces that the plane is “for the first time in history flying over the recently renamed Gulf of America. Please enjoy the flight, and we are now about to head westbound to Super Bowl 59.”

Mr. Vance, a 2013 graduate of Yale Law School, has repeatedly argued in recent years that presidents like Mr. Trump can and should ignore court orders that they say infringe on their rightful executive powers. While his post did not go that far, it carried greater significance given that he is now vice president.

The post may also offer a window on the administration’s thinking toward the orders against it as Mr. Trump has openly violated numerous statutes, like limits on summarily firing officials and effectively dismantling U.S.A.I.D. and folding it into the State Department. It also raised the question of whether the administration would stop abiding by rulings if it deemed them to be illegitimately impeding his agenda.

Mr. Vance’s post did not cite any specific ruling. But many of Mr. Trump’s allies have denounced an order early on Saturday prohibiting Trump political appointees and associates of Mr. Musk’s so-called Department of Government Efficiency initiative from gaining further access to the Treasury Department’s payments system.

Earlier in the day, Mr. Vance reshared a post by Adrian Vermeule, a Harvard Law School professor who has argued for strong presidential powers, and who wrote, “Judicial interference with legitimate acts of state, especially the internal functioning of a co-equal branch, is a violation of the separation of powers.”

Professor Vermeule appended his comment to a post by Senator Tom Cotton, Republican of Arkansas, who called the order about the Treasury Department “outrageous” and branded the judge who had issued it an “outlaw” who should be barred from hearing additional cases involving the Trump administration.

Notably, however, Mr. Cotton did not call for Mr. Trump to defy the order. Rather, he said an appeals court should “immediately reverse” it.

The second Trump administration’s brazen pattern of blowing through myriad apparent legal limits has prompted debate about its intentions. One theory is that it is deliberately setting up test cases that would ultimately pave the way for the Supreme Court’s Republican-appointed supermajority to expand presidential power by striking down the statutes as unconstitutional.

But the escalating pace of courtroom clashes has raised the question of what would happen if Mr. Trump simply started ignoring decisions he did not like, rather than appealing them. The result would be a constitutional crisis.

In the same social media post, Mr. Vance also cited types of decision-making by executive branch officials that he portrayed as outside the legitimate purview of courts.

“If a judge tried to tell a general how to conduct a military operation, that would be illegal,” he wrote. “If a judge tried to command the attorney general in how to use her discretion as a prosecutor, that’s also illegal.”

It has been more common for arguments to arise about the scope and limits of executive power in the context of statutes enacted by Congress, and where the line should be drawn between lawmakers’ ability to regulate the government and a president’s exclusive constitutional authority. For example in the George W. Bush administration, the president’s lawyers declared that Mr. Bush could lawfully disregard laws like a ban on torturing detainees, citing its broad view of his power as commander in chief.

But Mr. Vance has repeatedly asserted that presidents should ignore court orders they believe intrude on their own view of their constitutional authority.

In a 2021 appearance on a podcast, Mr. Vance, then running for a Senate seat in Ohio, said that if Mr. Trump returned to the White House in 2025, he should “fire every single midlevel bureaucrat, every civil servant in the administrative state, replace them with our people.”

He continued: “And when the courts — because you will get taken to court — and when the courts stop you, stand before the country like Andrew Jackson did and say: ‘The chief justice has made his ruling. Now let him enforce it.’”

In an interview on ABC News in February 2024, Mr. Vance, who was then the junior senator from Ohio, was asked whether he thought the president could defy the Supreme Court. Yes, Mr. Vance replied, if a ruling cut into a president’s rightful constitutional powers. He invoked a hypothetical example to lay out his reasoning, describing a decision that forbade a president, in his role as commander in chief, to fire a particular general.

“This is just basic constitutional legitimacy,” Mr. Vance said. “You’re talking about a hypothetical where the Supreme Court tries to run the military.”

He doubled down, in an interview with Politico Magazine the following month, that a president should ignore the Supreme Court if it stopped him from dismantling the federal bureaucracy.

“If the elected president says, ‘I get to control the staff of my own government,’ and the Supreme Court steps in and says, ‘You’re not allowed to do that’ — like, that is the constitutional crisis,” Mr. Vance said. “It’s not whatever Trump or whoever else does in response. When the Supreme Court tells the president he can’t control the government anymore, we need to be honest about what’s actually going on.”

Senator Andy Kim, Democrat of New Jersey, echoed Mr. Booker during an interview with NBC. If Democrats do not supply the votes for continued federal funding — signaling their opposition to Mr. Trump’s unilateral budget cuts, staff firings and restructuring of federal agencies — it would be Mr. Trump and Republicans who would be responsible for the government shutdown, Mr. Kim said.

“I would be the last person to want to get to that stage,” Mr. Kim said of a possible government shutdown. “But we are at a point where we are basically on the cusp of a constitutional crisis.”

The two Democrats’ allusion to the government shutdown in March reflects the limited options that their party has in checking Republicans, who are in control of all levers of federal government. It also shows their willingness to use the March funding deadline as an important bargaining tool to limit Mr. Trump’s sweeping action in tearing apart federal agencies funded and established by Congress.

In the past three weeks, Mr. Trump has tried to shutter the U.S. Agency for International Development; ordered the federal financial watchdog, Consumer Financial Protection Bureau, to cease “all supervision and examination activity”; tried to pause all federal loans and grants; suggested that the Federal Emergency Management Agency be shut down; and paused tens of billions of dollars in energy and environmental spending authorized by Congress.

Republicans in the House have a very slim majority. Speaker Mike Johnson cannot afford to lose more than three Republican votes to pass a spending package in March that reflects varying demands of his caucus.

During the last two years of the Biden administration, when Republicans controlled the House, dozens of right-wing members of the party who wanted deep cuts to government spending rebelled against Mr. Johnson and voted against keeping the federal government funded. Mr. Johnson had to work with Democrats in passing bipartisan spending bills that maintained funding at the levels of previous years.

Representative Hakeem Jeffries, Democrat of New York and the House minority leader, said last week that he was willing to work with Republicans in passing a similar bipartisan spending bill, but only if partisan measures for defunding certain agencies were “choked off” of that bill.

However, Mr. Johnson indicated on Sunday that he had no interest in pushing through a bipartisan bill. He said he would instead work toward a Republican spending package that all 218 members of his caucus could agree on.

“The reconciliation process which we are spending all the time on right now is by design effectively a partisan exercise,” Mr. Johnson said on Fox News. He was referring to the fast-track process for budget bills that would allow Republicans to avoid a Senate filibuster, which normally requires 60 votes to end.

Some members of the House Republican caucus are still skeptical that they can agree on a bill by March 14. Representative Chip Roy, Republican of Texas and the policy chair of the far-right Freedom Caucus, said on Friday that chances were “pretty low” that the Republicans could agree on a spending package by the March deadline. In January, Mr. Roy defied both Mr. Trump and Mr. Johnson by giving a fiery speech against his Republican colleagues, calling them “asinine” for working with Democrats in increasing the federal debt limit.

Still, Mr. Johnson said he remained optimistic that he could unite the Republicans in pushing through a partisan spending bill with the narrowest House majority since 1910.

“We can get this job done,” he said. “We have time. It’s early February, and the deadline is March 14.”

“Employees and contractors are to work remotely unless instructed otherwise from our Acting Director or his designee,” said the notice, a copy of which was reviewed by The New York Times.

Russell Vought, who now leads the Office of Management and Budget, was appointed late Friday as the consumer bureau’s acting director. Mr. Vought was an architect of Project 2025, the conservative blueprint for radically remaking the federal government.

The order to shutter the agency’s headquarters follows another order that Mr. Vought issued Saturday, telling agency employees to halt nearly all their work, including their regulatory supervision of banks and other financial companies.

The consumer protection agency, created by Congress in 2011 as a financial industry watchdog, cannot be closed without congressional action, but its director can freeze most of its actions by halting enforcement, weakening or repealing regulations and softening its supervision of banks and other lenders.

Yesterday, scholars predicted that the changes would eviscerate funds that had been used to advance research that helped sequence the human genome, quell some cancers and keep the United States at the forefront of medical advances.

The president also said that he would be stripping clearances for Letitia James, the New York attorney general, and Alvin L. Bragg, the Manhattan district attorney, both of whom have brought cases against him. Ms. James is also leading a group of 19 attorneys general in a lawsuit to stop Mr. Trump’s administration from allowing Elon Musk’s cost-cutting initiative from gaining access to the Treasury Department’s payment and data systems.

The new list of targets is the latest round of retribution Mr. Trump has lodged against his perceived political rivals and others who participated in high-profile legal cases against him. For many of those identified, it would be a largely symbolic action, but it could prevent the officials from getting into federal buildings or retrieving classified materials.

Mr. Blinken, the highest ranking official targeted, did not respond to a request for comment.

Mr. Trump did not provide specifics about what he sought to restrict from the officials. Mr. Trump called Mr. Blinken, the former secretary of state, a “bad guy” and said he wanted to “take away his passes.” Of others, Mr. Trump said his intent was “to take away every right they have.”

Taking questions from reporters aboard Air Force One on Sunday, Mr. Trump confirmed his decision, and denied it was a form of retribution.

“If there are people that we don’t respect, if there are people that we thought that were breaking the law or came very close to it in previous years, we do it,” he said of stripping clearances. “And we’ve done it with some people, we’ve done it with Biden himself.”

Mr. Trump’s remarks came on the heels of an announcement in a social media post on Friday that he was revoking Mr. Biden’s security clearances as payback to Mr. Biden, who did the same to him four years ago. Mr. Biden cited Mr. Trump’s “erratic behavior” as the basis for his decision, after he refused to accept the results of the 2020 election and incited a riot at the U.S. Capitol to overturn its results. On Friday, Mr. Trump accused the former president of setting the precedent in 2021, and cited a special counsel report that questioned Mr. Biden’s mental acuity.

“JOE, YOU’RE FIRED,” he wrote on social media.

Among other officials Mr. Trump identified in his New York Post interview for revocation were Jake Sullivan, the former national security adviser, and Lisa Monaco, the former deputy attorney general who coordinated the Justice Department’s investigation into Mr. Trump’s role in the Jan. 6, 2021, attack on the Capitol. Mr. Trump also targeted Andrew Weissmann, Mark Zaid and Norm Eisen, lawyers who have been outspoken critics of Mr. Trump.

Some of those on the latest list expressed little concern that Mr. Trump’s actions would affect them or their duties.

In a statement, Ms. James’s office brushed off the move as “just another attempt to distract from the real work the attorney general is doing to defend the rights of New Yorkers and all Americans.”

“What security clearance?” the statement quipped.

Mr. Zaid, in a statement Saturday, said that under existing law, he was entitled to due process, including being informed why he was being targeted after being trusted with classified information for more than 25 years.

“I’m honored by President Trump bestowing upon me a Red Badge of Courage, but if he and his partisan minions think this will deter me from holding them accountable to the rule of law, they are sadly mistaken,” he said.

“This highly politicized action reflects far worse upon the Trump administration than it does me,” he added.

Michael Crowley contributed reporting.

Waltz said it was appropriate to fold the agency into the State Department, and that he did not think by imperiling aid across the world the U.S. would give Russia and China an opportunity to expand their influence, as many national security experts and officials have warned.

The minute-long video will feature actual Secret Service agents and was produced in part by Michael Bay, the director of action movies like “Transformers” and “Armageddon,” an agency spokesman said. The video cost $1.5 million to $2 million, a figure in line with other Secret Service recruiting productions, the spokesman, Anthony Guglielmi, said.

The new Secret Service director, Sean Curran, leaned on a relationship with Mr. Bay, and the ad was produced over the course of nine days. The video was produced with Scott Gardenhour.

“In this role, part of my vision is to recruit and retain the most elite work force, and I recognized the void to do it expediently,” Mr. Curran said in a statement.

Secret Service agents are part of a group of hundreds of federal law enforcement officers, as well as those from state and local agencies, charged with securing the Super Bowl, held this year at the Superdome in New Orleans. Even before a deadly ramming attack in the city on New Year's Day left dozens killed or wounded, the authorities had planned to install additional safety measures. White House officials said that Mr. Trump was planning to attend Sunday’s game.

The Secret Service, which celebrates its 160th anniversary in 2025, has labored to recruit and retain agents, especially the past few years. According to federal data, at least 1,400 of its 7,800 employees left across the 2022 and 2023 fiscal years. This was the largest exodus from the agency in about two decades.

And those mass departures came before 2024, which was one of the hardest years the agency had faced, with a long presidential campaign and threats against Mr. Trump that intensified the need for security measures not previously extended to presidential candidates.

The staffing issue came into sharper focus after an attempted assassination of Mr. Trump at an outdoor rally in Butler, Pa., in July. Multiple investigations into how a 20-year-old gunman was able to climb upon a roof with a direct line of sight to Mr. Trump found that agents were stretched thin and morale was low.

Mr. Trump has called for hiring freezes across much of the federal government in an effort to evaluate the efficiency of the work force and where to cut costs. For now, the Secret Service has not been affected by these measures.

Senator Andy Kim, Democrat of New Jersey, echoed Booker’s sentiments during an appearance on NBC’s “Meet the Press” today. “I would be the last person to want to get to that stage, but we are at a point where we are basically on the cusp of a constitutional crisis,” he said.

Noem repeated President Trump’s false claim that Venezuela is deliberately releasing prisoners and those with severe mental health issues to the United States, as she defended the immigration crackdown under the second Trump administration.

Noem repeated President Trump’s baseless claim that the Biden administration has deliberately delayed or obstructed disaster payments to red states and counties.

The dozens of lawsuits fall into four main categories.

Immigration

The Trump administration’s crackdown on immigration — both legal and illegal — has resulted in at least 10 lawsuits, seven of which challenge his executive order revoking universal birthright citizenship. The plaintiffs seeking to defend the 14th Amendment’s longstanding guarantee to birthright citizenship include two groups of state attorneys general, nonprofits representing pregnant mothers, and an attorney from Orange County, Calif., who is representing his pregnant wife.

So far, the judges hearing these cases have been skeptical of Mr. Trump’s move, issuing two preliminary injunctions that have put the president’s order on ice. But one of the cases yet to be heard is before Judge Timothy James Kelly of the District of Columbia, who was nominated to the bench by Mr. Trump.

The other lawsuits against the president’s immigration policies challenge immigration agents’ authority to enter houses of worship; a memo that speeds up and broadens the scope of deportations; and an order that makes it harder for refugees to claim asylum in the United States. On Friday, San Francisco and other cities sued to block an executive order that would withhold federal funds from cities that do not assist with enforcing Trump administration immigration policies.

Budget Freezes and Firings

This category of litigation will likely grow as the administration attempts to assert its control over federal employees, lay the groundwork for potential mass firings and withhold spending that has been previously appropriated by Congress.

Mr. Trump’s attempt to freeze as much as $3 trillion in federal funding has run aground in two cases, one filed by a group of nonprofits in conjunction with Democracy Forward, and another by a group of 22 state attorneys general. An effort to gut the United States Agency for International Development is also at least partially on hold.

The administration’s “Fork in the Road” offer, sent by email to roughly two million federal employees by the government’s Office of Personnel Management, encouraging them to resign, was blocked, for now, by a Massachusetts judge on Thursday.

Three lawsuits challenge Mr. Trump’s effort to overhaul the civil service, stripping away job protections from tens of thousands of employees and giving the White House unilateral firing authority if they fail to “faithfully implement administration policies.”

Other lawsuits challenge the Trump administration’s attempts to unilaterally fire a member of the National Labor Relations Board, one of several agencies that are supposed to be independent of the executive branch. A lawsuit to stop Elon Musk’s team from accessing sensitive data at the Treasury Department yielded an agreement to do so for now.

Transgender Rights

Two lawsuits challenge an effort by the Trump administration to force the transfer of transgender women in federal prisons to men’s housing, and to deny them gender-transition medical care. One of those suits led to a restraining order that would temporarily keep the new policy from being carried out.

Out of more than 150,000 federal inmates, fewer than 50 are transgender women who are housed in women’s facilities, according to an administration official.

Other lawsuits address Mr. Trump’s attempts to ban transgender people from serving in the military, to deny federal funding from hospitals that offer gender-transition care to people under the age of 19, and to prevent transgender people from having their identities reflected on their U.S. passports.

Jan. 6 Investigators

Two groups of F.B.I. agents and bureau employees sued to block Mr. Trump from releasing the names of agents and staff members who participated in the investigations into the Capitol riot on Jan. 6, 2021, trying to head off what they fear is a looming purge. On Friday, the government agreed not to release the names while the case was being heard by Judge Jia M. Cobb of the District of Columbia, a nominee of President Biden.

Charlie Savage, Zach Montague, Madeleine Ngo and Eileen Sullivan contributed reporting.

“The courts really are the front line," said Skye Perryman, the chief executive of Democracy Forward, which has filed nine lawsuits and won four court orders against the Trump administration.

The multipronged legal pushback has already yielded quick — if potentially fleeting — results. Judicial orders in nine federal court cases will, for a time, partially bind the administration’s hands on its goals. Those include ending automatic citizenship for babies born to undocumented immigrants on U.S. soil; transferring transgender female inmates to male-only prisons; potentially exposing the identities of F.B.I. personnel who investigated the Jan. 6, 2021, attack on the Capitol; coaxing federal workers to accept “deferred resignation” under a tight deadline; and freezing as much as $3 trillion in domestic spending.

The judiciary’s response to the legal challenges is continuing through the weekend. On Friday afternoon, Judge Carl Nichols, a district judge nominated by Mr. Trump. said he would issue a temporary restraining order halting the administrative leave of 2,200 employees at the U.S. Agency for International Development and the looming withdrawal of nearly all of the agency’s workers from overseas.

Also, late on Friday night, Judge John D. Bates, a nominee of President George W. Bush, rejected a request by a coalition of unions for an emergency order blocking Elon Musk’s team from accessing Labor Department data. While that case is ongoing, Judge Bates’s ruling was the first victory for Mr. Trump’s new administration in federal court. In the early hours of Saturday, U.S. District Judge Paul A. Engelmayer, one of President Obama’s nominees, restricted access by Mr. Musk’s government efficiency program to the Treasury Department’s payment and data systems, saying access would risk “irreparable harm.”

Judges have not minced words. In Seattle last week, a district judge issued the second nationwide injunction blocking Mr. Trump’s order to end universal birthright citizenship. “The Constitution is not something with which the government may play policy games,” Judge John C. Coughenour said. Such a change, he added, could be made only through amending the Constitution. “That’s how the rule of law works.”

But while the executive branch is entrusted with the capacity for swift, decisive action, the judiciary is slow by design, and the legal opposition to Mr. Trump’s opening moves may struggle to keep up with his fire hose of disruption.

“Last night I was eating dinner with my family with an earpiece in my ear listening to a conference call and trying to be a dad at the same time,” Attorney General Rob Bonta of California said in an interview on Friday. “It’s hard work, but we’re not asking anyone to feel sorry for us. This is what we signed up to do.”

Mr. Trump’s first three weeks in office have yielded scores of executive orders to upend American foreign aid, domestic spending and social policy, many in open defiance of existing law. Without buy-in from or even consultation with the legislative branch of government, the president has wielded unilateral executive power in an attempt to dismantle parts of the government, override regulations governing civil service, overturn more than a century of precedent on immigration law, seek possible vengeance on his perceived enemies, and roll back liberal advances made in diversity and equity and transgender rights.

“No president should be able to rewrite 120-plus years of interpretation of the Constitution with a stroke of a pen,” said Dan Rayfield, Oregon’s attorney general, in an interview. “That is the existential threat.”

Some legal experts see the executive branch’s deliberate effort to push the boundaries of legality as a bare-knuckle strategy to overwhelm the president’s opposition and eventually win at least some precedent-shattering decisions from the conservative Supreme Court.

“The administration seems to have wanted challenges that consume a ton of resources — of opponents, courts and public attention — even as members of the administration know the provisions do not square with the law that exists,” said Judith Resnik, a professor at Yale Law School.

To Mr. Trump’s backers, the president’s orders are well within the powers outlined in the Constitution’s second section on the executive branch. It is the judicial pushback, they say, that is overstepping the constitutional boundaries laid out in the third section on the judiciary.

“President Trump is not stealing other branches’ powers,” said Mike Davis, who heads the Article III Project, a conservative advocacy group. “He is exercising his Article II powers under the Constitution. And judges who say he can’t? They’re legally wrong. The Supreme Court is going to side with Trump.”

Sunday on X, Vice President Vance made a provocative post that seemed to suggest that when it comes to the legality of the White House’s orders, judges do not have the final say. “Judges aren’t allowed to control the executive’s legitimate power,” he wrote.

Mr. Vance’s post “opens the door to a potentially dangerous path,” said Quinta Jurecic, a fellow at the Brookings Institution and a senior editor at Lawfare. “What Vance’s wording suggests here, without directly saying it, is that the executive could potentially respond to a court order by saying to the court, ‘You’re unconstitutionally intruding on my authority and I’m not going to do what you say.’”

“At that point,” Ms. Jurecic said, “The Constitution falls apart.”

As of Sunday afternoon, there was already at least one indication that existing court orders issued by federal judges to block Mr. Trump’s executive actions were not immediately changing the administration’s behavior on the ground. An emergency motion filed Friday by 22 state attorneys general before Judge John J. McConnell Jr. in Rhode Island district court claims an “ever-changing kaleidoscope of federal financial assistance that has been suspended, deleted, in transit, under review, and more,” despite a court order from Judge McConnell on Jan. 31 to end the funding freeze.

Further, the states say, the administration is claiming it can still freeze billions of dollars that are due under the Inflation Reduction Act and the bipartisan infrastructure act.

The Justice Department has until the end of Sunday to reply to the emergency motion.

According to the White House, Mr. Trump’s electoral victory in November gives him a mandate to exercise extraordinary power, narrow as the popular vote margin was.

“Every action taken by the Trump-Vance administration is fully legal and compliant with federal law,” Harrison Fields, a White House spokesman, said in a statement. “Any legal challenge against it is nothing more than an attempt to undermine the will of the American people.”

That should, in fact, be for the courts to determine — if Mr. Trump abides by their decisions.

Final judgments won’t come any time soon. Judge Coughenour’s injunction blocking Mr. Trump’s executive order to end automatic citizenship for children born on U.S. soil has already been appealed by the Justice Department to the U.S. Court of Appeals for the Ninth Circuit.

The ascent of some cases through the trial courts, to the appellate courts, and then to the Supreme Court could take months. Those lengthy battles will be political as well as legal, pitting a president who sees himself as the almost invincible leader of a populist movement against attorneys general, almost all Democrats, with their own ambitions, some legal scholars say.

“The attorneys general swung into action quickly. If they eventually prevail in court and in public opinion, they will reap political dividends for their perceived defense and vindication of their citizens’ rights,” said Akhil Reed Amar, a professor at Yale Law School.

If the attorneys general are using the campaign against Mr. Trump to burnish their own political futures, Mr. Amar added, that too is by design. “Our Constitution was designed so that ambition would counter ambition,” he said. “That is how the framers drew up the blueprint.”

Those pursuing the cases say they are unsurprised by the task ahead. Parallel efforts by Democracy Forward and the Democratic attorneys general to prepare for a second Trump presidency have been underway since early 2024. Now, coalitions of plaintiffs huddle on Slack long after midnight to prepare complaints in response to the administration’s latest moves. For the most part, the attorneys general have presented a united front, with some occasional last-minute jostling to decide who will get top billing as one of the leaders of the case, and in which venue it will be filed.

The one surprise factor? Elon Musk, the billionaire businessman who has been handed extraordinary — and possibly illegal — powers to cut and reshape the government, with no real title or Senate confirmation.

Matthew J. Platkin, New Jersey’s attorney general, called Mr. Musk “the one wild card” thrown at them.

“I’m not even sure Trump knows what he is doing,” Mr. Platkin said of Mr. Musk. “He’s an unelected billionaire running around government, slashing huge amounts of the work force and behaving in all kinds of potentially illegal ways.”

In legal filings, the Justice Department has argued that Mr. Musk’s associates are acting lawfully as employees detailed to agencies across the government and that they are under the authority of acting cabinet members.

The states have “special solicitude” as plaintiffs, a doctrine that draws on a 2007 Supreme Court ruling. That doctrine, which has carried less weight in recent years, makes it easier for states to bring lawsuits claiming that their rights or the rights of their citizens have been violated. It may be harder for those same states to apply that doctrine in claims against Mr. Musk’s teams, which operate at the federal level and affect the states less directly, according to lawyers familiar with the effort by attorneys general.

But that wrinkle did not stop Judge Engelmayer from siding, for now, with Letitia James, attorney general of New York, and 18 other Democratic attorneys general in their effort to keep Mr. Musk’s teams out of sensitive Treasury Department systems.

They argued that giving the government efficiency team access would violate the Constitution, and harm states that rely on the Treasury Department to fund child support payments and recover debts.

“I think right now we’re in the midst of a constitutional crisis,” said Ms. James, when the lawsuit was announced last week.

Ms. Resnik, the Yale Law School professor, said that while she expected the legal system to be “resilient,” it was hard to overstate the stakes for the judiciary in the coming weeks and months.

“Unbounded power is the antithesis of the U.S. Constitution,” she said. “That point is on display every time you enter the U.S. Supreme Court, where etched in stone are the words: ‘equal justice under law.’”

Jenna Russell, Laurel Rosenhall, Charlie Savage, Chris Cameron, Jacey Fortin and Hurubie Meko contributed reporting. Seamus Hughes contributed research.