You may have never heard of the National Nuclear Security Administration, but its work is crucial to your safety—and to that of every other human being on the planet. If Elon Musk’s Department of Government Efficiency (DOGE) hasn’t yet come across the NNSA, it surely will before too long. What happens after that could be alarming.

As recently as yesterday morning, Musk made clear that DOGE will go line by line through the government’s books looking for fat targets for budget-cutting, including those that are classified—especially those that are classified. DOGE employees are bound to notice NNSA, a 1,800-person organization that sits inside the Department of Energy and burns through $20 billion every year, much of it on classified work. But as they set out to discover exactly how the money is spent, they should proceed with care. Musk’s incursions into other agencies have reportedly risked exposing sensitive information to unqualified personnel, and obstructing people’s access to lifesaving medicine. According to several nuclear-security experts and a former senior department official, taking this same approach at the NNSA could make nuclear material at home and abroad less safe.

The NNSA was created by Congress in 1999 in order to consolidate several Department of Energy functions under one bureaucratic roof: acquiring fissile material, manufacturing nuclear weapons, and preventing America’s nuclear technology from leaking. It has all manner of sensitive information on hand, including nuclear-weapon designs and the blueprints for reactors that power Navy ships and submarines. Even the Australian Navy, which has purchased some of these submarines, is not privy to their precise inner workings, James Acton, a co-director of the Nuclear Policy Program at the Carnegie Endowment for International Peace, told me.

So far, the people who work for DOGE have not wished to be slowed down by cumbersome information-security protocols. Late last week, they reportedly demanded access to a sensitive Treasury Department system that controls government payments. When the most senior civil servant at the Treasury raised security concerns, DOGE engineers were undeterred, according to The New York Times. They were happy to blast ahead while he resigned in protest.

The employees at DOGE are reportedly working seven days a week, on very little sleep. This slumber-party atmosphere isn’t a great fit for the sober and secretive world of nuclear weapons, where security lapses are hugely consequential. I spoke with three former officials and nuclear experts about what might happen if DOGE were to take a too-cavalier approach to the NNSA. None believed that Musk’s auditors would try to steal important information—although it is notable that not everyone at DOGE is a federal employee, many lack the security clearance to access the information they are seeking, and Musk had to be stopped from hiring a noncitizen. Nuclear-security lapses don’t need to be intentional to cause lasting damage. “When access to the NNSA’s sensitive systems is not granted through proper channels, they can be compromised by accident,” the former senior official at the Department of Energy, who requested anonymity to discuss internal matters, told me. “You could stumble across some incredibly sensitive things if you are coming at it sideways.”

DOGE employees might try to avoid file systems that are known to contain nuclear-weapons designs. But they could still create some risk simply by inquiring into the ways that the NNSA spends money abroad, Acton said. (Overseas expenditures have been a focus for DOGE.) The NNSA helps other governments keep highly enriched uranium secure within their own borders, and also arranges for them to ship it to the United States for safekeeping. The details of these agreements may include information about the degree to which a country’s uranium is enriched, its precise whereabouts, and the nature of the security systems that protect it—all of which are very sensitive. If one of Musk’s recruits were to access this information on their personal laptop, they could expose those secrets to hackers or spies.

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A terrorist in possession of such information could find it easier to steal material for a nuclear device, Acton said. Even the mere perception that DOGE was not minding proper security protocols could hinder the NNSA’s relationships with other countries, which are essential to its nonproliferation work. These countries may not feel like they can trust the U.S. during a security breach or other kinds of emergencies.

One nuclear-security expert with more than 10 years experience told me that he’s worried that DOGE employees will poke around in personnel records at the NNSA, as they have at other federal agencies. (The expert did not wish to be identified, because he has previously worked with the United States government and governments abroad.) As part of a larger inquiry into which employees are most productive and who gets paid what, they could potentially access the “SF-86” forms that federal employees fill out when applying for a security clearance. Those may contain information about a person’s vulnerabilities that would be useful to the hostile foreign governments that hope to recruit NNSA employees to their cause.

[Read: The growing incentive to go nuclear]

On a Monday-night conference call for concerned federal workers organized by Representative Don Beyer of Virginia, a federal contractor who works with the Energy Department asked what to do if DOGE demands access to classified nuclear data. They wouldn’t be able to complain to the inspector general. Donald Trump reportedly fired the one who oversees the Department of Energy on his fourth day in office. On the call, they were told to speak with security officials at their agency. But this is cold comfort: When DOGE employees tried to access a secure system at USAID that included personnel files, John Voorhees, that agency’s director of security, confronted them. The DOGE employees threatened to call the U.S. Marshals, and in the ensuing standoff, DOGE prevailed. Voorhees and his deputy were placed on administrative leave.

None of this is to say that the NNSA should be exempted from questions about its budget. The agency likely overspends on some things, as any bureaucracy will. But nonexperts will struggle to determine what is essential and what is excessive in its highly specialized and technical realm. Building nuclear weapons is not like making widgets. DOGE can try to root out waste, but it should take its time and avoid the break-it-to-rebuild-it approach that Musk tends to prefer. A tech-start-up mindset might be dangerous, the former official told me: “That doesn’t work with nuclear weapons.”

As Elon Musk set out to upend the federal bureaucracy on behalf of Donald Trump, he reached out to Trump’s team with an unusual request: U.S. law generally prohibits noncitizens from working for the federal government, but Musk was hoping to make an exception for Baris Akis, a Turkish-born venture capitalist with a green card who had become a close ally.

The answer, delivered privately by Trump’s advisers, was an unequivocal no, two people familiar with the decision told us.

Trump’s White House is in the business of deporting people, and bringing in a foreign national to help shrink the government’s American workforce would send a confusing message, one of these people said. (Neither Akis nor the White House responded to a request for comment.)

Musk and his team accepted the rejection and moved on, but the previously unreported exchange offers a glimpse into the complex dynamics of the Musk-Trump relationship, arguably the most consequential partnership in Washington. This story is based on interviews with six people who have worked closely with Trump or Musk or are directly familiar with their relationship, all of whom requested anonymity to describe private interactions.

The world’s richest man has established himself as a singular force in the administration’s effort to slash government programs, agencies, and federal employees. Yet as an unelected “special government employee,” Musk still relies on the president for his authority. Since sweeping into Washington alongside Trump, Musk has wielded enormous power. He has pressured federal employees into deferred resignations; dug into government data and financial systems; used his massive social-media platform, X, to pick fights and bully opponents; and fed the U.S. Agency for International Development “into the woodchipper,” as he boasted yesterday on X, or at least helped get the agency folded into the State Department. He believes that understanding and mastering the government’s computer systems is the key to overhauling and fixing the government. But he does so at Trump’s behest, at least for as long as he has the president’s blessing.

Trump has made a point in recent days of making clear his supremacy over Musk, and Musk, for all his influence, has found himself bending to the strictures of the White House. Musk’s private security team, for instance, must wait in the parking lot at the 1600 Pennsylvania Avenue campus when he goes to work in a conference room at the Eisenhower Executive Office Building because of the building’s own security protocols, one of the people familiar with the arrangement told us.  

“Elon can’t do and won’t do anything without our approval. And we will give him the approval where appropriate, and where not appropriate we won’t,” Trump said yesterday during a signing event in the Oval Office. “Where we think there is a conflict or there’s a problem, we won’t let him go near it.”

On Sunday, Trump exited Air Force One after arriving in Washington from Palm Beach, and praised Musk as a “cost-cutter” who was “doing a good job,” before establishing the hierarchy: “Sometimes we won’t agree with it, and we’ll not go where he wants to go.”

Trump’s somewhat pointed comments on Musk “are important,” a longtime Trump confidant told us, explaining that “there’s one president.” This person said that Trump had learned about how to work within the government during his first term, but “that’s not true of Elon.”

But Musk nonetheless has threatened to steal the spotlight from Trump in recent days, becoming the public face of the administration’s most disruptive moves, including an effort to force thousands of voluntary resignations from the federal workforce. Inside the West Wing, he has found many allies, having ingratiated himself with mid-tier Trump aides early in the transition, when he moved down to Trump’s private Mar-a-Lago club and established himself as an accessible, if quirky, presence. He regularly shared his cellphone number, including with younger staff, and spent his days sending around memes and ideas about overhauling the government, according to a person who saw the texts but who was not authorized to speak publicly.

Musk has a group of loyalists he often brings with him to each of his various government projects—a cadre Trump today praised as “smart people.” But, unlike many people with his net worth and renown, Musk “travels pretty light,” one person told us. Two people told us that, during the time he spent at Mar-a-Lago, they most regularly saw him with his young son X—“just that kid on his shoulders,” one of the people said—and sometimes X’s nanny.

Musk preempted Trump shortly after midnight Monday in a live broadcast on X with the announcement that the Trump administration would seek to shutter USAID based on his own team’s investigation of the agency. “As we dug into USAID, it became apparent that what we have here is not an apple with a worm in it,” Musk said. “What we have here is just a ball of worms.”

And he has continued to pick public fights with Democratic leaders despite his new day job as a government employee. He accused House Democratic leader Hakeem Jeffries of wanting to continue “waste fraud and abuse” after Jeffries attacked Musk’s leadership of Trump’s Department of Government Efficiency, which operates as a part of the Executive Office of the President. Musk also wrote on X that Senate Democratic leader Chuck Schumer was mad about his work “dismantling the radical-left shadow government.”

Musk’s decision to seek a special dispensation for a noncitizen adviser came after the Tesla CEO’s views on immigration policy became a flash point inside the president’s circle late last year. When Musk defended the practice of giving H-1B visas to highly skilled foreign workers, Trump allies including Steve Bannon attacked Musk as part of a group of “techno-feudalists” undermining American workers. Trump had previously been critical of the H-1B visa system, but eventually sided with Musk in the dispute. Musk also moderated his stance, calling for “major reform” to how the visas are granted.

Democrats, who have struggled to respond effectively to Trump in the first weeks of his second term, have become more focused on Musk as a potential weak point for the president, as polling has shown significant public concern about Musk. A late-January poll by Quinnipiac University found that 53 percent of voters disapproved of him playing a prominent role in the Trump administration, compared with 39 percent who approved. About one in five Republican voters disapproved of Musk’s role.

Because of his special-government-employee status, Musk’s time in government is expected to be limited. Employees under this status, who do not have to divest from outside conflicts of interest, are permitted to work no more than 130 days in a single year. Other members of Musk’s team, including Katie Miller, a Department of Government Efficiency adviser, are also working for the government under the temporary designation. (Musk is also close to Miller’s husband, White House deputy chief of staff Stephen Miller.)

Musk’s preferred work habits before entering the federal bureaucracy could provide a window into how he might continue to feed “into the woodchipper” programs and spending that he views as Washington bloat. During his time in the private sector, Musk tended to burrow into each of his companies on different days, a person familiar with his routine told us. Monday was for SpaceX, Tuesday was for Tesla, and Wednesday was for X.

This week, Sunday and Monday were clearly for USAID. By tomorrow and Thursday, however, he might be ready to turn his buzz saw elsewhere.

It took the Trump administration—and, really, Elon Musk—all of 10 days to dismantle USAID, the world’s single largest humanitarian donor. On January 24, a memo from the State Department ordered virtually every foreign-assistance program funded by the United States government to halt work for 90 days. Four days later, the State Department said that lifesaving humanitarian assistance should continue, and that special waivers could be granted to select programs. Nevertheless, soup kitchens stopped handing out food, clinics suspended care, and truckers paid through aid programs stopped delivering medicine.

Then came the purge. Early yesterday morning, the Department of Government Efficiency, a Musk-led group that has been announcing what stays and goes in Washington, told employees not to come to work. Musk posted on X an hour later, “We spent the weekend feeding USAID into the wood chipper.” More than 1,000 employees—including some in war zones—were locked out of their work accounts. Earlier today, Politico reported that nearly all of USAID’s Washington-based staff will soon be placed on leave, and ABC News reported that staff on foreign assignments are being evacuated.

USAID, which has distributed aid to hundreds of millions of people around the world for 60 years, estimates that it has extended children’s life expectancies by six years in many of the countries it works in. But its $40 billion in annual spending—about 0.7 percent of the U.S. budget—has been criticized for inefficiencies, and many Americans accuse the government of spending too much on foreign aid. Some of those critiques are arguably fair. In 2022, for example, USAID spent more than $100,000 on theatrical productions in Ireland and Colombia. (That said, Americans also tend to drastically overestimate the amount we spend on foreign aid.) USAID was established by Congress as an independent agency, and by law, only Congress can dissolve it. The White House, though, seems determined to do away with it as an independent agency; yesterday, Secretary of State Marco Rubio announced that he is now the acting head of USAID. If the agency is successfully subsumed by the State Department, it could, in theory, continue in a slightly diminished form—or be totally gutted. When reached for comment, a State Department spokesperson referred me to Rubio’s recent statements to the media. One of them read: “USAID may move, reorganize, and integrate certain missions, bureaus, and offices into the Department of State, and the remainder of the Agency may be abolished consistent with applicable law.”

So far, the administration has framed the foreign-aid pause as temporary. But even if much of USAID’s work is allowed to resume in a few months, the intricate global-health ecosystem being torn apart will not be easily repaired. Famine and disease—two of the issues against which USAID has made the most progress—don’t stop when funding does, and can spread disastrously in even a short window. Prior to the stop-work order, at least 220,000 people worldwide got their HIV medication every day at clinics supported by the U.S. government. Juli Duvall-Jones, who oversees an HIV clinic in eastern Ivory Coast, told me that the pregnant women her clinic serves are no longer receiving their daily treatment, meaning that some children will almost certainly contract HIV during birth or through breastfeeding. People who are exposed to HIV have only 72 hours—less than the amount of time many clinics have now been closed—to begin a medication regimen called post-exposure prophylaxis that can help prevent infection. A pause of any length in USAID-funded anti-HIV efforts will cause more people to contract the disease. Missing doses of treatment can make it less effective. Without treatment, the disease kills young people in about 12 years, and older adults even faster.

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The head of one aid group, who, like several aid workers I spoke with, asked that neither she nor the group be named for fear of permanently losing their USAID funding, told me that her organization—which, among other projects, treats severely malnourished children and babies in Sudan—is now scraping by on money diverted from other projects. Most aid efforts operate on extremely thin margins, so any pause in funding is felt almost immediately. “We can sort of keep it going for a few days,” she said. But once the money runs out, these children will lose the supplemental oxygen, fortified foods, and 24/7 medical supervision they need. Many, she said, will die in two to six hours.

As the 90-day pause drags on, longer-term consequences will start to become clear. In Uganda, the national government has stopped spraying insecticide and distributing bed nets to pregnant women and young kids; during the country’s next rainy season, which spans from March to May, malaria cases and deaths may spike. The Center for Victims of Torture, a global nonprofit, has furloughed most of its staff and stopped rehabilitation programs in Jordan, Uganda, and Ethiopia, including one for women among the estimated 100,000 raped in a recent war in Tigray, Ethiopia. Scott Roehm, CVT’s director of global policy and advocacy, told me that many of the center’s clients attempted suicide prior to getting help. He fears what will happen to people who have to stop their treatment—and those who never get help at all.

Right now, it seems unlikely that all or even most of USAID’s programs will resume at the end of April. Yesterday, Donald Trump said Ukraine should give America its lithium in exchange for aid, suggesting that programs that don’t give the U.S. an immediate win may be cut for good. The longer the pause lasts, the more devastating the effects will be, not just for aid recipients but also for Americans. The Famine Early Warning Systems Network, a monitoring tool funded by USAID, has been offline since Friday. Without it, aid workers may struggle to intervene early enough to prevent mass starvation, and farmers have lost a major tool for anticipating agricultural shocks. Michael VanRooyen, an emergency physician who has led humanitarian work in Darfur, Rwanda, and Ukraine, estimates that an extended pause in food aid could kill hundreds of thousands of people, many of them children. USAID workers leading the agency’s response to an active Ebola outbreak in Uganda were among those locked out of work systems. Without their involvement, the U.S. could miss signs that the outbreak is growing or changing—or even that a new pandemic is brewing.

Democratic lawmakers have started pushing back on the demolition of USAID. Yesterday, Brian Schatz, a Democratic senator from Hawaii, said in a statement that “dismantling USAID is illegal and makes us less safe,” and placed a blanket hold on nominees for State Department positions until USAID is back up and running.

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But if the agency is restored—next week, next month, or years from now—restarting its work won’t be as simple as turning the flow of cash back on. After the week USAID has had, staff might be hard to come by. According to one group of development workers tracking the fallout, the aid freeze has caused nearly 9,000 Americans and far more people around the world to lose their jobs. Many may decide to pursue work outside the humanitarian sector, which typically offers low pay and benefits. Even if the pause ends quickly, the federal government has given workers little incentive to return. Musk has called USAID “a criminal organization,” “a ball of worms,” and a “viper’s nest of radical-left Marxists who hate America.”

Whoever does come back to work will need to get back in touch with the people who lead local organizations (many of which have or will have gone defunct), the world leaders with whom they once partnered, and the people who shuttle supplies around the world. Susan Reichle, a foreign-assistance expert who served in every presidential administration from George H. W. Bush’s to Trump’s first term, told me that the pause has already broken trust that could take years to repair. “USAID staff are having to meet with ministers of health, ministers of power, ministers of education” to tell them that work has stopped, Reichle said. “And they can’t tell them if or when those partnerships will ever continue.”

Having a measured, humane debate about the way the U.S. distributes humanitarian aid is possible. It is in the country’s interest to spend aid money effectively. And the way the United States distributes global aid could certainly be improved. But the instant retraction of much of the world’s food and health-care infrastructure will create damage that cannot be undone. After three months, “many of those people will be dead, or so severely harmed and malnourished that it causes them irreversible and deep suffering,” Lawrence Gostin, the faculty director of Georgetown’s O’Neill Institute for National and Global Health Law, told me. A pause on saving lives means exactly that.