Michael Hayden doesn't run from a fight, which is just what seemingly awaits the 61-year-old Air Force general expected to be named the new CIA chief.

Weeks after the attacks of Sept. 11, 2001, the then-head of the National Security Agency was telling intelligence-gathering teams how they would fight back: White House-approved electronic monitoring, without court orders, of the international calls and e-mails of people in the United States when terrorism was suspected.

When The New York Times disclosed the program in December, triggering an uproar over its legality, Hayden plunged right in, defending the surveillance in a speech at the National Press Club.

"Frankly, people in my line of work generally don't like to talk about what they've done until it becomes a subject on the History Channel," Hayden said. "But let me make one thing very clear. As challenging as this morning might be, this is the speech I want to give."

Hayden ran the super-secret NSA from 1999 until last year, when he became the top deputy to the new national intelligence director, John Negroponte, who oversees the CIA and 15 other intelligence agencies.

It could prove a contentious battle to switch to the CIA, given the reaction from lawmakers on the Sunday talk shows. They said the CIA is a civilian agency and putting Hayden atop it would concentrate too much power in the military for intelligence matters.

Sen. Arlen Specter, R-Pa., the Judiciary Committee chairman, also spoke of using the Senate's role in the nomination process as "leverage" in finding out more than the Bush administration has provided so far about the warrantless monitoring.

But Hayden has shown he is not one to shy away from difficult situations.

Matthew Aid, a historian who is writing a book on the NSA, said when a deputy director resisted change at the agency, Hayden sent her to London to fill a liaison job with the British.

Hayden's public defense of the warrantless surveillance program showed his aggressiveness and his ability to dispense with a general's jargon.

Even critics of the surveillance praise his clarity. For them, the problem is in the message.

"I think he is part of the White House spin machine on the NSA program," said California Rep. Jane Harman, who has known Hayden for years and is the senior Democrat on the House Intelligence Committee. But, she said, he does an excellent job in his briefings.

Harman said Hayden loves Shakespeare and, with their spouses, attended a play at Washington's Shakespeare Theater.

Hayden had a blue-collar upbringing in Pittsburgh. There was his father's work at a manufacturing company; his brother's employment as a truck driver; Hayden's part-time job as a cabbie to make ends meet after earning bachelor's and master's degrees in history from Duquesne University.

He had Air Force assignments in Bulgaria, South Korea and Germany.

The CIA job opened up Friday, when director Porter Goss resigned in the latest evidence of a White House shake-up.

"He can be an SOB if he wants to be," said Aid, a historian working at the private National Security Archive who is writing a book on the NSA.

Aid said Hayden's transfer of the deputy to London came about because the subordinate was leading the opposition to changing the NSA — from a Cold War agency that intercepted radio communications to one the lives in the world of the Internet and cell phones.

"He didn't say 'You guys are the veterans here, you run the place," Aid said. "He said, 'You're for us or against us. Those who stood with the deputy retired or got kicked sideways."

In his defense of the surveillance program at the National Press Club. Hayden sounded like he was speaking to ordinary Americans, not official Washington.

"These are communications that we have reason to believe are Al Qaeda communications, a judgment made by American intelligence professionals, not folks like me or political appointees," he said.

"So let me make this clear. When you're talking to your daughter at state college, this program cannot intercept your conversations. And when she takes a semester abroad to complete her Arabic studies, this program will not intercept your communications," Hayden said.

James Bamford, who has written two books on the NSA, said if Hayden gets the CIA job, he once would again have to overhaul an intelligence agency that has low morale and is trying to find its place in the fight against terrorism.