Homeland Security Secretary Janet Napolitano on Friday announced her resignation after four years running the Department of Homeland Security and is expected this week to be approved as the next president of the University of California.

Napolitano is expected to formally leave DHS in September. Her departure will add to a number of existing leadership vacancies at the department, including the deputy secretary position following Jane Holl Lute’s resignation in May.

DHS Secretary Janet Napolitano. Photo: DHS

DHS is also without leaders at its Intelligence & Analysis bureau, Customs and Border Protection, the Domestic Nuclear Detection Office, the Office of Inspector General and others, although these agencies do have acting chiefs.

During her tenure, Napolitano introduced an efficiency initiative aimed at avoiding more than $1 billion in costs, overseen the deployment of additional Border Patrol agents to the nation’s borders, helped usher in a risk-based security screening program at aviation checkpoints while also adding the infamous body scanners, elevated cyber security as a key pillar of homeland security, and ensured that the department is quick to respond to natural disasters across the country.

Early in her service, Napolitano halted a border security technology program that relied on cameras and radars in fixed locations to monitor portions of the Southwest border in favor of a more diverse technology program, the main portions of which have yet to be acquired and deployed. She has rankled Republicans by saying the border is more secure than ever although the department hasn’t developed more sensitive metrics to better measure border security.

Rep. John Mica (R-Fla.), a critic of DHS, tweeted yesterday that Napolitano’s resignation “comes not a minute too soon,” and called for Congress to dismantle the “monstrous” DHS in favor of a smaller “security-based entity.”

Rep. Michael McCaul (R-Texas), chairman of the House Homeland Security Committee, a critic of the Obama administration’s border security record as well as its unwillingness to isolate violent Islamic extremism as the root of terrorism facing the United States, nonetheless said he respects Napolitano and thanked her for her service.

“Ten years after the creation of the department, it is critical that its mission isn’t undermined by politics or political correctness,” McCaul said in a statement. “The border is not secure, and the threat of terrorism is not diminishing. The vision and actions of the department must reflect that reality.”

McCaul’s counterpart in the Senate, Tom Carper (D-Del.), praised Napolitano for her leadership and dedication. Carper also lauded her for improving information sharing and pre-screening programs, boosting preparedness and recovery for natural and man-made disasters, and building up DHS’ cyber security capabilities.

Sen. John McCain (R-Ariz.), also a critic of some of the administration’s border policies, also tipped his hat to Napolitano for serving the nation with “honor,” her work ethic and her integrity.

Shortly after Napolitano’s resignation announcement Friday morning, names of potential successors began to surface including former Connecticut Senator Joseph Lieberman (I/D), Federal Emergency Management Administration Chief Craig Fugate and New York City Police Commissioner Raymond Kelly among others.

A special committee of the Univ. of California charged with searching for a new president of the university system nominated Napolitano last Friday. The university’s Board of Regents will meet on July 18 to decide whether to approve her for the job.

The Univ. of California consists of 10 campuses, five medical centers, three affiliated national laboratories and a statewide agricultural and natural resources program.

Before becoming DHS Secretary, Napolitano was the governor of Arizona. She was also that state’s attorney general and a U.S. District Attorney for Arizona.