Call it the Monday Afternoon Massacre. After firing Secretary of Homeland Security Kirstjen Nielsen on Sunday, President Donald Trump purged the agency’s senior management on Monday. According to CBS News, Trump secured the resignation of U.S. Citizenship and Immigration Services Director Lee Cissna, DHS Undersecretary for Management Claire Grady, and DHS General Counsel John Mitnick. He also fired U.S. Secret Service Director Randolph “Tex” Alles. Trump adviser Stephen Miller, an immigration hard-liner, reportedly masterminded the DHS purge as part of an effort to crack down on immigration at the southern border.

Just how much worse, though, can Trump’s immigration policies get? The president, after all, persuaded Nielsen to carry out Trump’s ghastly family separation policy at the southern border (while publicly claiming that the policy did not exist). During her tenure, Nielsen also designed a plan that strictly limited the number of asylum-seekers allowed to enter the United States. And she implemented what was ultimately ruled to be an unlawful policy to prevent immigrants from applying for asylum if they entered the country illegally. The New York Times reports that Nielsen drew the line at Trump’s “clearly illegal” demands, including “blocking all migrants from seeking asylum.” She also reportedly refused to resume family separations, despite Trump’s entreaties, because she did not want to violate a court order that currently prohibits the practice.

Nielsen, in other words, carried Trump’s immigration crackdown as far as she could without risking contempt of court. Under her leadership, the agency engaged in horrific human rights abuses and violence against innocent migrants, including children. Nonetheless, it could, indeed, get worse. Trump’s “near-systematic purge” at “the nation’s second-largest national security agency,” as one senior administration official put it to CNN, is an ominous indication that Trump will now brook no independent judgment at DHS. He wants an agency that does exactly what he asks. And what he asks is frequently cruel, brutal, and lawless.

Consider the coup that Miller allegedly engineered on Monday. Under federal law, the DHS undersecretary for management should have become acting DHS secretary when Nielsen resigns later this week. As of Monday morning, Claire Grady filled that position. A career civil servant who previously worked at the Department of Defense and the Coast Guard, Grady specializes in weapons acquisitions. She also served as acting deputy DHS secretary, working on immigration and counterterrorism issues. An apolitical defense expert, Grady was perfectly qualified to lead DHS until Congress confirmed a new secretary.

But Trump didn’t want Grady; he wanted Kevin McAleenan, commissioner of Customs and Border Protection. It’s easy to see why. Under McAleenan’s leadership, CBP repeatedly broke the law to implement Trump’s first travel ban, earning a rebuke from DHS’ Office of Inspector General. McAleenan is a strong proponent of a border wall as well as new laws to curb asylum-seekers’ entry into the country. He infamously failed to inform Congress that a 7-year-old girl died in CBP custody when he testified before the Senate just three days after her death.

To elevate McAleenan, Trump simply ousted Grady, then ignored the line of succession to leapfrog McAleenan to the head of DHS. (An Obama-era executive order allows him to do just that.) McAleenan appears eager to resume family separations, speaking vaguely of a “binary choice” that would let migrant parents either surrender their children to CBP or go into long-term detention as a family. This pseudo-compromise is really just an effort to get around a court order that has blocked family separations since June (though they have continued in smaller numbers).

Trump and Miller plainly expect that McAleenan will rubber-stamp illegal policies that Nielsen was unwilling to execute. Presumably, they hope McAleenan will approve Trump’s idea of expanded family separation, which CNN’s Jake Tapper reported on Monday. Tapper wrote that Trump wants families separated even if they enter the U.S. at a port of entry and are legally seeking asylum. (“He just wants to separate families,” a senior administration official said.) Nielsen refused to carry out this policy, which reportedly contributed to her termination. “At the end of the day,” the administration official told Tapper, “the President refuses to understand that the Department of Homeland Security is constrained by the laws.” Given that McAleenan refused to let CBP be constrained by the laws during the first travel ban, Trump may hope he will take the step that Nielsen would not and defy the courts to punish migrants.

It’s more difficult to understand why Trump fired Cissna and Mitnick, aside from general dissatisfaction with the direction of the agency. (Similarly, no one seems to know why he fired Alles, the Secret Service chief.) Cissna, in particular, was an efficient hawk who successfully limited the number of immigrants allowed in the country. It was Cissna who gutted the U.S. refugee program and beefed up the denaturalization task force while making it easier for the government to initiate deportation proceedings and deny visas to foreign nationals. Cissna also spearheaded the “public charge” rule, which would deny green cards to immigrants if their family members use a public benefit, including food stamps.

Shortly before his termination, Politico reported that Miller asked Cissna “to launch more experimentally and legally questionable policies,” but Cissna declined “to overstep legal boundaries.” His effective efforts to curb immigration and penalize immigrants could not spare him from the purge.

If Nielsen and Cissna were not sufficiently extreme, it is alarming to consider what might come after them. Both bent the law as far as they could to implement hugely controversial and frequently vicious policies to further Trump’s nativist goals. It wasn’t enough for the president. With their ousters, DHS is entering a new era, one in which the agency will do whatever Donald Trump and Stephen Miller think it can get away with.