The resignation of Janet Napolitano, secretary of the Department of Homeland Security (DHS), expands a leadership void that needs to shrink soon to avoid hurting the agency's progress on cybersecurity, experts say.
Napolitano announced Friday that she was resigning to become president of the University of California system. She plans to begin her new job in September.
During her tenure, Napolitano and Deputy Secretary Jane Holl Lute, who recently left her post, made cybersecurity a national priority, an effort first started by Napolitano's predecessor, Michael Chertoff.
Threats driving the need for stronger defenses include cyberattacks on the nation's critical infrastructure, financial institutions and private industries. Experts and congressional leaders have pointed to China as the leading origin of cyberespionage campaigns against U.S. government agencies and corporations.
Napolitano's departure brings the number of vacant or soon-to-be vacant leadership positions at DHS to 15, seven of them requiring Senate confirmation, Foreign Policy magazine reported.
While it is not unusual to have leadership positions vacant in any government agency, the number at DHS is reaching a point where it could lead to "significant operational and management risks to that department, and also diminishes its accountability to the U.S. Congress," the report said.
Stewart Baker, a former assistant secretary for policy at DHS, described Napolitano's exit as a "big loss," because it leaves the department's top two positions vacant.
"The presence of Rand Beers [Under Secretary for National Protection and Programs at DHS] will provide some continuity, but institutional memory on cybersecurity and terrorism issues is getting pretty thin," Baker, who is now a partner at the law firm Steptoe & Johnson, told CSOonline.
[Also see: Cybercrime 'much bigger than al Qaeda']
Last month, President Barack Obama nominated Alejandro Mayorkas, the director of U.S. Citizenship and Immigration Services, to replace Lute. Mayorkas is awaiting Senate confirmation.
Napolitano's successor will need to work quickly in continuing the department's push to get private industry to voluntarily share information on cyberattacks with government agencies. In February, Obama issued an executive order directing agencies to share threat intelligence with the private sector.
"You want your secretary to be able to walk in and convene meetings with boards, CEOs and general counsels," Jacob Olcott, principal consultant for cybersecurity at Washington, D.C.-based Good Harbor Security Risk Management, said. "That's really what the role of the secretary should be, and then to make sure the department has the appropriate budget and vision."
While not an expert in cybersecurity to begin with, Napolitano has gotten high marks from experts for being a quick study and moving the department forward in tackling the issue. "She showed an interest in learning the issues and became a very strong advocate for the administration," Olcott said.
Her successor will have to move as fast in driving the next phase, which includes establishing standards and best practices for protecting critical infrastructure, such as the nation's power grid, and building better collaboration between government and the private sector.
Nevertheless, Kevin Coleman, cyberterrorism expert for The Technolytics Institute, said getting the right replacement for Napolitano was most important. "The wrong candidate could have far greater consequences than a short time delay in filling the spots," he said.
Read more about security leadership in CSOonline's Security Leadership section.