Kirstjen Nielsen out as Trump’s Homeland Security Secretary

Kirstjen Nielsen is out as secretary of the Department of Homeland Security, President Donald Trump tweeted Sunday, amid ongoing controversy over a surge in Central American asylum-seekers crossing at the US-Mexico border.

“Secretary of Homeland Security Kirstjen Nielsen will be leaving her position, and I would like to thank her for her service,” he tweeted.

It’s unclear whether Nielsen resigned on her own volition or was pressured. Trump said Kevin McAleenan, the current US Customs and Border Protection Commissioner, will become acting secretary.

In her resignation letter, Nielsen said she had determined it was the right time for her to step down, and suggested that her successor would need changes to existing immigration law before the border could be secured.

“I hope that the next Secretary will have the support of Congress and the courts in fixing the laws which have impeded our ability to fully secure America’s borders and which have contributed to discord in our nation’s discourse,” she said. “Our country and the men and women of DHS deserve to have all the tools and resources they need to execute the mission entrusted to them.”

Nielsen’s departure is the latest to roil Trump’s ever-changing cabinet. The president’s frustration with Nielsen’s job performance steadily grew throughout last spring and summer, when the number of families apprehended crossing the US-Mexico border began skyrocketing.

His anger boiled over last fall as several Central American migrant caravans traveled to the US, and it has continued to simmer as the growing number of migrant families have overwhelmed Border Patrol agents.

Nielsen’s sudden departure is reportedly part of a sweeping effort by Stephen Miller, one of Trump’s advisers and one of the staunchest immigration hardliners left in the office, to overhaul Trump’s top DHS officials and implement a harsher crackdown on immigration policies, according to CBS News.

Last week, Trump also abruptly withdrew his nomination of Ronald Vitiello as Immigration and Customs Enforcement director and told reporters he had wanted to go in a “tougher direction.”

In recent weeks and months, Trump has declared a national emergency at the border to obtain funds to build his border wall, sought to cut aid to Central American countries, and threatened to close down the entire border unless Mexico prevented the migrants from crossing.

Read more:Trump mocks asylum-seekers at the border, says they ‘look like they should be fighting for the UFC’

The face of border arrests and family separations

Trump, who frequently uses the monthly border apprehension statistics as a barometer for the effectiveness of his immigration agenda, largely blamed Nielsen for the uptick in border-crossings, even as she defended his more controversial policies, including the “zero-tolerance” immigration policy that separated more than 2,500 migrant children from their parents.

Nielsen also drew heavy scorn from Trump critics last June, when she held a combative press briefing at the White House and denied that the Trump administration had created a family-separation policy, even as families were being forcibly separated en masse.

“Why would I ever create a policy that purposely does that?” Nielsen said. “This administration did not create a policy of separating families at the border.”

The controversy prompted several Democratic lawmakers to call on Nielsen to resign at the time.

Read more: Closing the border would put the US economy at a ‘standstill’ and actually worsen illegal border crossings. Here’s how it would affect food prices, jobs, and Americans’ everyday lives.

Nielsen’s DHS tenure has been dotted with conflict and uncertainty in the months since she was hired to replace John Kelly, her former boss who was hired as the White House chief of staff.

She reportedly drafted a resignation letter in May after Trump berated her in front of cabinet officials and accused her of failing to adequately secure the US’s southern border.

Nielsen later addressed the reports by saying Trump was “rightly frustrated” about border security, and that she shared his frustration.

Cracking down at the border

Yet even as she has defended Trump’s more controversial policies and statements, Nielsen also reportedly sought to rein him in on some of his wilder proposals.

Nielsen has reportedly complained that Trump and his allies don’t understand the nuances of immigration and asylum law, which prevent the federal government from indefinitely detaining migrant children and deporting them and their parents quickly.

Nielsen has also mocked Trump’s repeated calls for a border wall, according to The Washington Post, and said privately it’s unlikely to ever be built.

When Nielsen recently tried to push back against Trump’s calls to close the US-Mexico border entirely, Trump grew impatient and frustrated, aides told The Post in November.

Her apparent skepticism for Trump’s most extreme border proposals, combined with her history as a Kelly aide and Bush administration alumna, have prompted Trump to question her loyalty.

According to The Post, Trump calls Nielsen a “Bushie,” referring to her past work for President George W. Bush as a special assistant to the president for prevention, preparedness, and response.