In his first month in the White House, Stephen Miller learned a valuable lesson from a mentor. As one of his first acts as president, Donald Trump had signed an executive order banning travel to the United States from several majority-Muslim countries, and mass protests were breaking out across the country. Law-enforcement officials, who had received little guidance on how to carry out the order, were flummoxed, and the administration was swiftly taken to court. Chief strategist Steve Bannon, who helped craft the order alongside Miller, was nevertheless delighted by the self-created maelstrom. When journalist Michael Wolff later asked Bannon why the ban had been implemented so recklessly, Bannon suggested the chaos was part of the fun. “So the snowflakes would show up at the airports and riot,” he replied.

Whereas Bannon made controversy his calling card, Miller has operated in a more shadowy—and effective—manner, gradually applying leverage and using shrewd personnel decisions to implement his draconian vision on immigration policy throughout the West Wing and government agencies. Some measures, like his role in the travel ban or the Trump administration’s callous family-separation policy, have been obvious. “It was really a shock to a bureau whose mission is to help refugees,” Anne Richard, a former assistant secretary of state for Population, Refugees and Migration, said of the travel ban. “I knew the Trump administration from the campaign was hostile to refugees. I did not anticipate that they would move so quickly, even before there was a Secretary of State.” As one senior Senate staffer explained, in the early months of the Trump administration “it was very dramatic and people knew what was happening and you could just see it visibly.”

Other maneuvers to restrict legal immigration have been slightly more subtle. Last September, Miller played a leading role in slashing the refugee admissions cap to 45,000—less than one-half the 110,000 ceiling set under President Barack Obama, and the lowest level since 1980. Now, he has reportedly revived his push for another cut, to a cap as low as 15,000 refugees. Earlier this week, the 32-year-old senior adviser was reported to be focused on an even more ambitious project: imposing strict limits on legal immigration, as well as on individuals seeking asylum from war, famine, and prosecution. “The administration seems to delight in picking on the most vulnerable people,” David Robinson, the former assistant secretary for the Bureau of Conflict and Stabilization Operations at the State Department, told me, enumerating the ways in which the resettlement process had been logjammed. “Pretty soon you are going to have a trickle and not a stream.” Currently, the U.S. is on pace to admit around 22,000 refugees this fiscal year. Defenders of the policies argue that the cuts offset a surge in asylum seekers, while critics dismiss the notion as a manufactured crisis. “By 2020, I would not be surprised if we just don't have this program anymore,” said Jennifer Quigley, an advocacy strategist for refugee protection at Human Rights First. “I wouldn’t be surprised if it’s 5,000 next year and then zero.” (When asked about the negotiations for next year’s refugee cap, an administration official said in a statement, “We are not going to get ahead of the president’s policy.”)

Nearly a dozen current and former administration officials I have spoken with in recent weeks describe the latest negotiations over the refugee-admissions cap as one of the more insidious examples of Miller’s efforts to curtail immigration to the United States. (Miller, a lifelong culture warrior, first made his name in conservative circles with an impassioned op-ed raging against the preponderance of Latino students who “lacked basic English skills” in his high school.) “It’s part of a very coherent, effective, and successful plan. It’s not easy to do hard things in our government,” a former official at the Department of Homeland Security explained. “Our government is huge . . . it’s kind of constructed to slow things down and to make sure that individuals don’t wield excessive power. It’s got lots and lots of checks and balances, so it’s really difficult to pull off something like what they’ve pulled off, and they’ve done it.” There are, after all, hundreds of career civil servants who have dedicated their lives to helping the estimated 69 million refugees in the world, only a minuscule portion of whom ever gain sanctuary in the United States. But Miller has found ways to hijack the machinery of the government to undermine these agencies’ core mission. “Now, it’s sort of like the termite approach, which is you place people inside and you have them basically eat away in a more quiet way, subtly inside,” the senior Senate staffer continued. “It’s not as transparent to the outside world, and they just sort of destroy programs they don’t care about.” (The White House declined multiple requests for comment.)