WASHINGTON (AP) — President Barack Obama is calling back a trusted counterterrorism adviser from his first term by nominating former top Pentagon lawyer Jeh Johnson as secretary of homeland security.

Obama plans to announce Johnson's nomination Friday. He must be confirmed by the Senate before taking over the post most recently held by Janet Napolitano, who stepped down in August to become president of the University of California system.

As general counsel at the Defense Department during the wars in Iraq and Afghanistan, Johnson was an aggressive advocate on a number of complex and contentious legal issues. He oversaw the escalation of the use of unmanned drone strikes, the revamping of military commissions to try terrorism suspects rather than using civilian courts and the repeal of the military's ban on openly gay service members. He also mapped out the legal defense for the American cross-border raid into Pakistan that killed Osama bin Laden.

A senior Obama administration official on Thursday confirmed Johnson's selection, first reported by The Daily Beast. The official was not authorized to speak about the nomination on the record and spoke on condition of anonymity.

The official said Obama chose Johnson because of his experience as a national security leader. The official noted that Johnson oversaw the work of more than 10,000 lawyers and was responsible for reviewing every military operation approved by the president and defense secretary.

Johnson is not as well versed in the immigration and disaster response side of the Homeland Security Department, although the administration official pointed out the Pentagon also coordinates federal relief to respond quickly to disasters.

Former Defense Secretary Leon Panetta praised Johnson's selection Thursday, saying he has "impeccable judgment, leadership qualities and high ethical standards."

At the Pentagon, Johnson was involved in the decision to move Army Pfc. Chelsea Manning from a military jail in Quantico, Virginia to Fort Leavenworth, Kansas. Supporters of Manning, the young soldier who leaked thousands of classified documents to WikiLeaks, said conditions at the military jail in Virginia were too harsh.

Johnson sparked criticism when he said in a speech at Britain's Oxford University last November that the war on terror was not an endless conflict and that the U.S. was approaching a "tipping point" after which the military fight against al-Qaida would be replaced by a law enforcement and intelligence operation.

"War must be regarded as a finite, extraordinary and unnatural state of affairs," Johnson said. "In its 12th year, we must not accept the current conflict, and all that it entails, as the new normal."

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Associated Press writers Alicia A. Caldwell and Lolita C. Baldor contributed to this report.

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