WASHINGTON (AP) - A Senate hearing on John Brennan's nomination to head the CIA could lay bare some parts of the secret war against al-Qaida: lethal drone strikes from covert bases against even American terror suspects, harsh interrogation methods and long detention of suspects without due process. Some of the practices produced revulsion among some in Congress and the public, but the outcry has been muted because Brennan and others say that these harsh and secretive methods have saved American lives. Those issues will be front and center in the Senate Intelligence Committee hearing Thursday for Brennan - a chance for him to answer criticism that he backed the detention and interrogation policy while he served at the CIA under President George W. Bush, charges that stymied his first attempt to head the intelligence agency in 2008. In answers to questions from the Senate Intelligence Committee before the hearing, Brennan said he was "aware of the program but did not play a role in its creation, execution, or oversight," and added that he "had significant concerns and personal objections" to the interrogation techniques. He wrote that he voiced those objections to colleagues at the agency privately. Brennan also described how individuals are targeted for drone strikes, saying whether a suspect is deemed an imminent threat - and therefore appropriate for targeting - is made "on a case-by-case basis through a coordinated interagency process" involving intelligence, military, diplomatic and other agencies. He defended the missile strikes by Predator or Reaper drones as a more humane form of war. Aides have portrayed him as cautious in their use, restraining others at the CIA or military who would use them more often, even though as the White House's counterterror czar he has presided over an explosion of drone strikes in Pakistan, Yemen and Somalia. Less than 50 strikes took place during the Bush administration while more than 360 strikes have been launched under President Barack Obama, according to the website The Long War Journal, which tracks the casualties. Administration officials say Brennan would further limit the use of drones by the CIA and leave the majority of strikes to the military. The CIA's drone strikes primarily focus on al-Qaida and Taliban targets in the tribal regions of Pakistan, while the military has launched strikes against al-Qaida targets in Yemen and Somalia. The CIA also carries out strikes in Yemen from a base in Saudi Arabia, including one that killed three American citizens: Anwar al-Awlaki, his 16-year-old-son and Samir Khan. The location of the base was first disclosed by The New York Times in a story that previewed Brennan's hearing, highlighting the sensitive issues that the hearings will bring into the open. The Associated Press first reported the construction of the base in June 2011 but withheld the exact location at the request of senior administration officials. Once it was disclosed, the AP considered the agreement to be no longer in place. Democrats in Congress have begun to express stronger opposition to the use of drones, but on Wednesday Obama found an unlikely ally in Republican Sen. Lindsey Graham, who expressed his "100 percent" support of the use of drones against terror suspects. Brennan will also face questions about charges that White House officials leaked details of the administration's national security policies, including its cyberattacks against Iran's nuclear infrastructure, to burnish Obama's standing as commander in chief ahead of last year's presidential election. Brennan himself has come under fire by Republican lawmakers who believe he gave the media too many details in news conferences after the 2011 killing of al-Qaida mastermind Osama bin Laden. The Obama White House launched a sweeping investigation led by two Justice Department lawyers in response to congressional ire over the leaks. White House officials have defended briefings given by Brennan as authorized and backed by the president himself, who they say has the ultimate authority to declassify information. Brennan told the Senate committee in his written answers that he was questioned as a voluntary witness in the leak investigation. He also said that in his current role, he is "vigilant about not disclosing classified intelligence matters with unauthorized persons, including reporters and media consultants." House Intelligence Committee Chairman Mike Rogers, R-Mich., who has strongly criticized the administration's release of information on its national security programs, predicted "lots of questions about leaks and detention" at the Senate hearings, but he also predicted that Brennan would ultimately be confirmed. When he joined the White House as the top counterterrorism advisor in 2009, Brennan publicly decried the interrogation practices, saying they backfired and produced more terrorists, leading him to urge the newly elected president to stop them. That represented an evolution from earlier statements to the media. Brennan told the committee in his written responses that "a lot of information, both accurate and inaccurate, came out of interrogation sessions conducted by (the) CIA," but that he believed the techniques were legal but "counterproductive." "These techniques would not be used again by the CIA if I were the director," he wrote. After Obama's election, he returned to the government payroll, in 2009, as the White House counterterror czar, where he made public his views on harsh interrogation. Brennan was nominated to replace CIA director David Petraeus, who resigned late last year, citing an extramarital affair. Sen. Dianne Feinstein, D-Calif., chairwoman of the Senate Intelligence Committee, has signaled she will support Brennan's nomination, but congressional staffers say both she and her Republican counterparts will ask Brennan to explain publicly if he objected to the interrogation program, and whether he believes it produced any useful intelligence. Congressional aides said she would seek Brennan's support in future, if the committee votes to declassify portions of it after the White House and CIA finish reviewing the document. Feinstein and others will also keep pressing Brennan and the White House to show them the classified legal memo that outlines specifically when drones and other lethal strikes can be employed against al-Qaida. An unclassified Justice Department White Paper was made public this week, outlining America's authority to kill suspected terrorists with drones, even U.S. citizens, if a case can be made by the CIA or military that they are linked to al-Qaida and have taken part in plots against Americans. AP National Security Correspondent Lara Jakes and Associated Press writer Donna Cassata contributed to this report. Dozier can be followed on Twitter (at) kimberlydozier.