President-elect Joe Biden’s choice of Alejandro Mayorkas to lead the Department of Homeland Security thrilled immigrant advocates on Monday and won praise from former DHS leaders who described him as a savvy department veteran who would try to stabilize the organization after years of front-office turmoil under President Trump.

Biden has pledged to reverse many — if not most — of Trump’s executive actions on immigration, and Mayorkas’s nomination signaled that the president-elect is looking for someone experienced in both immigration policy and politics, anticipating the issue will remain a source of intense partisanship.

The son of Cuban Jews who fled Fidel Castro’s 1959 Revolution, Mayorkas would be the first immigrant and first Hispanic American to lead DHS if the GOP-controlled Senate confirms him. Mayorkas’s first public statement after the announcement was an indication that immigration, for him, is deeply personal.

“When I was very young, the United States provided my family and me a place of refuge,” Mayorkas wrote in a tweet. “Now, I have been nominated to be the DHS Secretary and oversee the protection of all Americans and those who flee persecution in search of a better life for themselves and their loved ones.”

He followed with another tweet, saying it is an honor to be nominated and that he will “work to restore faith in our institutions, and protect our security here at home.”

Mayorkas, 60, who goes by “Ali,” came to the United States as a baby and was raised mostly in Los Angeles. His mother was a Romanian Jew who escaped the Holocaust and arrived in Cuba in the 1940s, where she met his father, who was of Sephardic heritage.

When he was DHS deputy secretary under President Barack Obama in 2015, Mayorkas was one of the government officials who participated in negotiations with the Cuban government after the United States normalized relations with Havana, a policy that Trump promptly reversed.

President-elect Joe Biden named Alejandro Mayorkas as homeland security secretary to serve in his administration on Nov. 24. (The Washington Post)

Current and former DHS officials who have worked with Mayorkas praised him as someone familiar with the department and capable of handling the challenge of low employee morale at several of its key agencies. DHS went through a period of unprecedented turmoil under Trump, with five different leaders, only two of whom were Senate-confirmed. Many of DHS’s top posts were left vacant or filled with leaders in acting roles during the past four years.

Created after the Sept. 11, 2001, terrorist attacks as an agency with a focus on counterterrorism, DHS under Trump became largely an instrument of domestic policy. As Trump ordered the construction of a giant steel barrier along the Mexico border, Trump senior adviser Stephen Miller used the department to carry out a wide-ranging, multiagency immigration crackdown.

The Biden administration is expected to try to return DHS’s focus to a broader range of concerns, including counterterrorism, cyber threats and the pandemic response.

Tom Ridge, who served as the first Secretary of Homeland Security under President George W. Bush, praised Mayorkas as “an exceptionally fine choice.”

“DHS has been somewhat of a political piñata during this administration, so someone who has served as deputy secretary and overseen the U.S. Citizenship and Immigration Services portfolio will bring a level of confidence to staff and to Congress and will do a great job restoring morale to a much-beleaguered agency,” Ridge said in an interview. “He will hit the ground running.”

Republicans could take issue with Mayorkas’s role in the creation of the Deferred Action for Childhood Arrivals (DACA) program, and they are likely to bring up a 2015 DHS inspector general report that found Mayorkas inappropriately helped several companies obtain employment visas. Mayorkas disputed those findings. He did not respond to a request for comment Monday.

Early in his career, Mayorkas served as an assistant United States Attorney in the Central District of California, and he specialized in prosecuting white-collar crime, such as the federal tax evasion and money-laundering case against Hollywood Madam Heidi Fleiss.

He was named a U.S. attorney in 1998 — the nation’s youngest top prosecutor at the time — and pursued cases involving all manner of fraud, such as money laundering, immigration scams and cybercrime.

Obama tapped Mayorkas to serve as the director of U.S. Citizenship and Immigration Services, and he won accolades in that role from advocacy groups and government officials. As deputy secretary at DHS under Jeh Johnson, Mayorkas oversaw a wide array of responsibilities that included the government’s response to hurricanes, immigration crises and disease outbreaks.

“All Mayorkas is as qualified as anybody to take on the leadership of DHS, one of the biggest and most difficult jobs in the U.S. government,” Johnson said. “He is a very hard working, smart and compassionate individual.”

Mayorkas most recently has worked as a litigator representing companies on behalf of WilmerHale, an international law firm. In his WilmerHale bio, Mayorkas touted experience “leading the U.S. Department of Homeland Security’s response to Ebola and Zika,” and lists that he heads WilmerHale’s Covid-19 Coronavirus Task Force.

John Sandweg, a former acting director of Immigration and Customs Enforcement who served with Mayorkas from 2009 to 2014, called Mayorkas an “ideal choice” to run the department, with his personal background, law-enforcement experience and deep knowledge of the nation’s immigration system.

It is likely that Biden’s administration will upend much of what Trump did on immigration; while the Trump administration said anyone could be deported, Biden has signaled that he would refocus ICE on people who pose a threat to public safety and national security.

“Ali is common sense,” Sandweg said. “Doesn’t mean he’s not going to make reforms, but every single decision he ever made, national security and public safety were at the top of his considerations. Even DACA, he made sure there were robust protections in place to preserve public safety.”

He said one of the things Mayorkas was proudest of creating was the USCIS Fraud Detection and National Security Directorate, to emphasize that vetting was crucial in giving out immigration benefits.

Mayorkas also presided over the Obama administration’s rollout of the DACA program, which granted work permits to undocumented immigrants brought to the United States as children. The rollout posed a challenge for DHS, which had to vet applicants but also needed to persuade undocumented immigrants that it was safe to come forward. More than 800,000 applied at the program’s peak.

Mark Hetfield, president and CEO of HIAS, an organization that aids refugees, said Mayorkas sits on the board and is “uniquely suited” to lead the agency “as the child of a Holocaust survivor, as a Latino and as a refugee and immigrant himself.”

“Ali is uniquely suited to rebuild public trust in the Department of Homeland Security, as he knows that America is at its greatest when we build bridges, not walls,” Hetfield said.