* Brennan defends use of drone strikes targeting Americans
* Denies giving away secrets or releasing classified material
* Protesters yell "Stop the drones," hearing briefly halted
* Committee expected to vote on nomination next Thursday (Updates with lawmakers, Brennan comments)
By Patricia Zengerle and Tabassum Zakaria
WASHINGTON, Feb 7 (Reuters) - John Brennan, President Barack Obama's nominee for CIA director, said on Thursday he did not try to stop waterboarding, an interrogation technique that some consider torture, as he faced tough congressional questioning on that issue, security leaks and the use of drones to kill U.S. terrorism suspects.
Lawmakers pressed Brennan on controversial counterterrorism tactics employed while he was a CIA official under former President George W. Bush, and others whose use he helps oversee in his current role as chief counterterrorism adviser to Obama.
The issue of the now-banned harsh interrogation techniques derailed Brennan's consideration for CIA director four years ago, and he met it head-on at his confirmation hearing before the Senate Intelligence Committee.
"I did not take steps to stop the CIA's use of those techniques. I was not in the chain of command of that program," Brennan said. "I had expressed my personal objections and views to some agency colleagues" about waterboarding, a form of simulated drowning, nudity and other techniques, he said.
"But I did not try to stop it, because it was something that was being done in a different part of the agency under the authority of others, and it was something that was directed by the administration at the time," he said.
DOCUMENTS FOR LAWMAKERS' EYES ONLY
In a bid to smooth congressional concerns about counterterrorism activities under his watch, Obama on Wednesday ordered the Justice Department to give House and Senate intelligence committees access to a classified legal opinion on killing U.S. terrorism suspects with drone strikes.
Brennan, 57, has been central in overseeing U.S. government policy on the use of the armed, unmanned aircraft in counterterrorism operations in the Obama administration.
But some, mostly Democratic, lawmakers are demanding that the White House provide more of the legal documents underpinning its position that Obama can order lethal strikes overseas on U.S. citizens suspected of terrorist activity.
The administration insisted that only lawmakers be allowed access to the classified Justice Department papers, which means the committee's lawyers are unable to read them.
Senator Dianne Feinstein, the intelligence committee's Democratic chairwoman, complained to Brennan that the committee's staff had been banned from seeing the administration's classified legal opinion.
"The reason for providing information just to committee members at times is to ensure that it is kept on a limited basis," Brennan said. "It is rather exceptional, as I think you know, that the Office of Legal Counsel opinion - or advice - would be shared directly with you."
The hearing was recessed briefly after Brennan started speaking because of protesters, who began yelling "Torture is always wrong" and "Stop the drones."
Some of the most intense questioning of Brennan came from liberal Democrats, not the conservative Republicans who have raised the strongest objections to one of Obama's other security nominees - Chuck Hagel, his choice to lead the Pentagon.
Civil liberties groups have criticized the drone program as effectively a green light to assassinate Americans without due process in the courts under the U.S. Constitution.
While he faced probing, and at times confrontational, queries from senators, Brennan seemed unflustered and gave little ground. He appears on track for approval by the committee and confirmation by the full Senate.
"I sat through a number of these hearings. I don't think I've ever heard anyone more forthright or more honest or more direct," Feinstein told Brennan. "I think you are going to be a fine and strong leader for the CIA."
After the hearing, Feinstein said she expects the committee to vote on the nomination next Thursday.
Senator Ron Wyden, an Oregon Democrat, expressed reservations about the drone program.
"Taking the fight to al Qaeda is something every member of this committee feels strongly about. It's the idea of giving any president unfettered power to kill an American without checks and balances that's so troubling," he said.
In an exchange with Wyden, Brennan defended the use of drone strikes to target Americans who joined al Qaeda.
"Any American who did that should know well that they in fact are part of an enemy ... and that the United States will do anything possible to destroy that enemy and to save American lives," he said.
In 2011 a drone strike killed U.S.-born Anwar al-Awlaki, described by U.S. investigators as a leader of al Qaeda's Yemen-based affiliate. His 16-year-old son, also a U.S. citizen, was killed in a separate drone strike in Yemen that year.
QUESTION OF LEAKS
Republicans questioned Brennan in detail about a Reuters story that reported he told former U.S. officials who are now television commentators that the United States had "inside control" over an alleged plot by al Qaeda's Yemen-based affiliate to destroy an airliner using an underwear bomb undetectable by the latest security technology.
A few hours after the Brennan conference call, one of the pundits, former White House adviser Richard Clarke, said on ABC TV that the administration had implied "that they had somebody on the inside" who was not going to allow the bombing plot to be carried out.
U.S. and European security officials later acknowledged that British Intelligence, with the help of U.S. and Saudi agencies, had succeeded in planting an informant inside the militant group, but that this undercover operation had to be terminated prematurely due to news leaks.
Brennan emphatically denied he had given away government secrets or released classified material on the conference call with the former officials.
He said that the serious leak was to the Associated Press about an airline bombing plot that had been disrupted. (Additional reporting by Susan Heavey, Jeff Mason, Matt Spetalnick and Mark Hosenball; Editing by Warren Strobel and Xavier Briand)