LANGLEY, Va. — John O. Brennan, director of the Central Intelligence Agency, on Thursday strongly defended C.I.A. officers who carried out brutal interrogation tactics against Qaeda suspects, describing agency interrogators as “patriots” and admonishing only those who went “outside the bounds” of Justice Department rules.

Speaking from inside the marble lobby of the C.I.A.’s headquarters, Mr. Brennan on Thursday challenged the conclusions of an excoriating report by the Senate Intelligence Committee that concluded the agency’s detention program had yielded little valuable information, and that the C.I.A. repeatedly misled the White House and Congress about the efficacy of the program. Mr. Brennan said that the C.I.A. detention program had value, even if it is “unknowable” whether useful intelligence was obtained as the direct result of brutal interrogation methods.

Unlike President Obama, Mr. Brennan pointedly refused to say that the methods — including waterboarding, shackling prisoners in painful positions, and locking them in coffin-like boxes — amounted to torture.

His characterization of the program on Thursday was a contrast to the remarks he made in 2009 while serving as Mr. Obama’s top counterterrorism adviser, when he said that the interrogation methods “led us astray from our ideals as a nation” and that “tactics such as waterboarding were not in keeping with our values as Americans.” Asked on Thursday about those comments, Mr. Brennan said he stood by them.