THURSDAY’S CONFIRMATION hearing for John O. Brennan as director of the CIA will give senators an opportunity to air a host of pent-up questions about the Obama administration’s secret warfare, including drone strikes in Pakistan, Yemen and Somalia. But the nominee should also be pressed on a more fundamental question: Does the secret war really have to be so secret?

As The Post and other news organizations have reported, Mr. Brennan has played a crucial role as the White House’s counterterrorism adviser in managing and regularizing the conduct of drone attacks by the CIA and the Pentagon’s Joint Special Operations Command in all three countries. The Post and Newsweek have reported that Mr. Brennan has developed a “playbook,” spelling out the rules for a “disposition matrix” that determines whether terrorist suspects should be targeted for killing. According to Newsweek’s Daniel Klaidman, “embedded in the document are the legal authorizations for pursuing the enemy far away from conventional battlefields in places like Yemen, Somalia, and now Mali.”

Though it has ordered hundreds of drone strikes that have killed thousands, the Obama administration has never disclosed the methodology in the playbook. It has not provided public reports on the targets and results of drone strikes and, in the case of Pakistan, still officially refuses to acknowledge them. It has refused to disclose the Justice Department memos authorizing the operations, including attacks on U.S. citizens, even though one of the administration’s early acts in 2009 was to release war-on-terror Justice Department memos drawn up by the George W. Bush administration.

This week a Justice “white paper” summarizing the legal case for targeting terrorists who are U.S. citizens was obtained by NBC News. But the underlying memo remains classified, and the paper adds only incrementally to a speech delivered nearly a year ago by Attorney General Eric H. Holder Jr.

If there is a compelling case for all of this secrecy, the administration has not made it. While clandestine drone strikes in Pakistan may have been necessary when the program began during the Bush administration, the attacks and their origin long ago ceased to be secret in any meaningful way. They are reported by the Pakistani press and hotly debated by the country’s politicians; what’s missing is official U.S. information.

As for the legal memos, we have argued before that, while the administration’s drone war against al-Qaeda is legal, its increasingly shaky political and diplomatic grounding would be strengthened if the administration were to disclose its justifications and allow them to be debated and ratified by Congress. The same goes for Mr. Brennan’s playbook: War should not be waged according to secret rules without legislative review or sufficient oversight. It was reported Wednesday night that Mr. Obama has decided to allow congressional intelligence committees access to the Justice memos, which would be a first step in the right direction.

Threaded through many of these issues is question of whether the CIA, rather than the military, should be carrying out acts of war. In the immediate aftermath of Sept. 11, 2001, there was some reason to rely on the agency’s paramilitary activities. But with the expansion of the military’s special operations, the justification for such CIA activity, which feeds the secrecy problem, is no longer apparent. Mr. Brennan should be asked why he should not refocus the agency on intelligence collection and leave military operations to the generals.