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Unlike H. R. McMaster, Rex Tillerson, and Nikki Haley, James Mattis was never going to go quietly. He has read too much history and is too cognizant of his duty for that. His letter of resignation was all the more devastating for its understatement. For more than a year, senior administration officials have constructed the fiction that the United States is following a foreign policy of competing with authoritarian powers. Anyone who has talked with one of these officials in private will be familiar with the mantra—look at the substance of the National Security Strategy, not the tweets. Never mind that the president never spoke of this strategy, even when he made remarks introducing it.

Mattis laid bare the reality. He wrote that his views “on treating allies with respect and also being clear eyed about malign actors and strategic competitors” make it impossible for him to continue to serve the president, because “you have a right to have a Secretary of Defense whose views are more aligned with your views on these and other subjects.”

In a post for Task & Purpose, Paul Szoldra, a former marine, pointed to a speech Mattis delivered in 2014, shortly after he retired from the Marine Corps. He was asked whether there was anything that would lead a four-star general to resign in protest. “You have to be very careful about doing that,” Mattis said. “The lance corporals can’t retire. And they’re going. That’s all there is to it.” He emphasized that he always expected to be heard by policy makers, but not to be obeyed. “My portfolio was narrower than the president’s. He was the commander in chief. He was voted in by the American people.” Be careful, he cautioned, because a leader’s first obligation is to that lance corporal. “You abandon him only under the most dire circumstances, where the message you have to send can be sent no other way. I never confronted that situation.”

That dire situation is now upon us. So what happens next?

President Donald Trump’s views are well known to anyone who cares to look. In his speeches over the past two years, he has consistently identified four threats to America—immigrants, alliances, trade deficits, and terrorism. (He used to talk a lot about North Korean nuclear weapons, as well, but appears to have since struck a de facto bargain with Kim Jong Un. North Korea has ceased testing missiles and nuclear bombs, and relations between the two countries have warmed.) Over three decades, Trump has consistently expressed admiration for authoritarian leaders, especially in Russia. But above all, Trump wants the freedom to do as he wants, when he wants, free from constraints. He wants to be indulged. He wants to be a king.

The turning point of the Trump administration came on July 17, 2017. For the first six months of his presidency, Trump largely deferred to the so-called axis of adults of Tillerson, McMaster, and Mattis. When he diverged from their advice—when, for example, he refused to endorse Article 5 of the North Atlantic Treaty while speaking at NATO headquarters—he soon backtracked under pressure. But on July 17 he had had enough. He was sitting through yet another interagency meeting, this time on the Iran nuclear deal, known as the Joint Comprehensive Plan Of Action. Not only did all of his advisers recommend staying in the deal—the three options in front of him required it. He agreed to effectively extend the deal one more time but demanded that the next time, he be given an option to withdraw.

After that meeting, Trump began to push back. He started giving orders unilaterally—to move the embassy to Jerusalem, to meet with Vladimir Putin, to meet with Kim Jong Un, and even to hold a military parade. But as long as the axis of adults remained in place, he was constrained. So he began to force them out. If there is a common theme behind the reshuffle, it is that Trump replaces independent thinkers with sycophantic loyalists or those too weak to stand up to him. If past practice is any guide, Trump will double down on loyalists when he replaces Mattis. Men such as John Bolton and Mike Pompeo do not agree with Trump on many issues, but they value their loyalty to him personally above their own views and they will never try to thwart his will.

Bolton learned this lesson early on. When he became national-security adviser, many observers commented on the irony that his first task would be to implement a policy of diplomatic outreach toward North Korea, something he opposed so vociferously in his previous time in government that President George W. Bush fell out with him over it. Three weeks into the job, Bolton tried to sabotage the talks by claiming that the administration was looking to the Libya model, whereby Muammar Qaddafi unilaterally disarmed. It was apparently intended as a dog whistle that would pass unheard by Trump but that would cause the North Koreans to sink the talks before they began. The North Koreans were furious, as intended. The South Koreans also noticed, though, and complained to Trump. Pompeo backed them up, and Trump was furious. Bolton was excluded from high-level meetings with North Korean officials and was only added to the Singapore summit at the last minute. He learned his lesson—he has not again explicitly worked against the president.

Bolton now focuses on the issues he is interested in and the issues Trump is interested in, but nothing else. Bolton is preoccupied by international law and made opposition to the International Criminal Court and other institutions one of his top priorities. One European diplomat told me that Bolton has spent exponentially more time on dealing with the Western Sahara territorial dispute between Morocco and the Algerian backed Polisario Front—a pet issue of his for decades, given United Nations involvement—than with post-conflict planning for Syria. Days before Trump’s announcement of a retreat from Syria, Bolton briefed European officials that the United States would be staying. Even more significant, Bolton has effectively abolished the interagency process by which major national-security decisions are made in formal consultations with the relevant departments, thus allowing Trump to freelance to his heart’s content.

When Pompeo became secretary of state, he faced a fateful choice: forge an alliance with Mattis, or indulge the president at every turn. He chose the latter course; Trump once remarked that Pompeo is the only person on his team with whom he never fights. This choice trapped Pompeo in a vise. He became secretary when morale was low. He has helped to rebuild the department, but he has dramatically shrunk the role of secretary of state. Foreign diplomats I’ve talked to describe him as the secretary for Iran and North Korea because he works on nothing else. Even on these issues, he will not stand up for himself.

The president’s decision to withdraw U.S. troops from Syria is widely seen as benefiting Tehran. Pompeo, along with Bolton, tried to convince Trump to change his mind, but they folded once he made his decision. Pompeo is particularly wary of opposing the president. On North Korea, he persists in embracing the myth that a process of denuclearization is under way despite all evidence to the contrary. This puts him in the awkward position of looking foolish and naive. It’s a dangerous place for someone who is so ambitious, which is maybe why he has become so testy in his conversations with journalists when questioned about North Korea.

When Bolton and Pompeo began, they believed that they could persuade Trump to accept them bringing some of the Never Trumpers who opposed the president during the election on to their staff. Those hopes were dashed when Trump rebuked Mike Pence for trying to hire Jon Lerner as his national-security adviser; Lerner had worked for an anti-Trump political-action committee during the campaign. Pence, for his part, has been even quieter than Bolton and Pompeo, refusing to take any stance, even in private, that is at odds with the president. The talent pool has been almost drained dry; there is no untapped reserve of experienced, qualified, Trump-supporting national-security aides. While many people have resigned, other senior officials are remaining in place because they are worried about the real-world consequences of their positions remaining vacant indefinitely, or being filled by someone unqualified.

We are left with a Cabinet that is weak, terrified, and myopic. Meanwhile, the president is empowered and unbound—but also insecure and desperate. Nothing can be ruled out anymore. The president is free to indulge his visceral instincts unchecked. The unilateral declarations on Syria and Afghanistan are just the beginning. It is quite possible that he will try to withdraw U.S. forces from South Korea and Germany, renege on Article 5 of the North Atlantic Treaty, or strike a comprehensive grand bargain with Xi Jinping over the objections of Japan.

It will surely get worse. As the revelations from Robert Mueller’s investigation inflict blow after blow and the subpoenas fly from House Democrats, Trump will become more erratic and dangerous in his decision making. Of all the resignations, the second most damaging after Mattis may be John Kelly. Few liberals shed a tear for him on his departure, but his flaws were largely counterbalanced by one vitally important redeeming feature—he was a stabilizing force on national security. He could check Bolton and channel Mattis. He could play interference. And now he is gone, replaced by Mick Mulvaney, who has no national-security experience.

America’s allies had hoped to ride out the next two years. Senior officials from multiple European and Asian allies told me that they had concluded by mid-2018 that they could engage with the administration but that things went off the rails whenever the president was directly engaged, which was usually on a foreign trip. They decided to deliberately reduce the opportunities for him to be involved. Thus, the 70th anniversary of the NATO summit would not be marked by a leaders’ summit, but would instead occur at the foreign-ministers level (it will be hosted by Pompeo in Washington, D.C.). The agendas for G20 and G7 summits are being pared back, frequently with the support of officials in Washington. But those plans count on an administration that checks Trump, not one that empowers him. It is very possible that America’s adversaries will try to take advantage of the disarray. If Putin or Xi makes a major move, such as trying to test America’s alliances, it will be soon.

With the hollowing out of the Trump administration, the onus now passes to Congress. In her book Troublesome Young Men, Lynne Olson tells the story of Conservative Party rebels in the 1930s who spoke up against their leader and brought Winston Churchill to power. One of the remarkable things about Trump’s first two years is that not a single up-and-coming Republican politician took a stand against the president. Other than John McCain, the only Republicans who did anything are either semi-retired (John Kasich) or retiring (Jeff Flake).

Even leaving morality to one side, that is surprising. Senators such as Tom Cotton see themselves as Trump’s successors, but some might have taken the other side of the bet, especially if they hope to be active in politics for the next two decades. If Trump fails and is discredited, those who paid a price for standing against him will be rewarded. Every defeat and every humiliation will be transformed into a badge of honor. There will be little reward for those who jump on the bandwagon after his fall has become inevitable. Republicans may have increased their majority in the Senate, but this dynamic could be a wild card. As Trump’s troubles deepen, the incentive for younger senators to become troublesome will grow. The confirmation hearings for Mattis’s successor will provide an early test of whether any have grown bold enough to break ranks.

There is a narrative arc to the Trump presidency—a radical, constrained by the system, who breaks out and follows his instincts. The next chapter is predictable. Possessing all the power he ever desired, he will be undone by his own character. All that remains to be seen is how, at what cost, and if his party will do anything to stop it.

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