Mr. Brennan has probably made some mistakes in the past, too, and that includes his apparent acceptance of harsh interrogation techniques of suspected terrorists during the Bush administration. But he also served as Mr. Obama's top advisor on counter-terrorism in the first term. After 25 years at the CIA, Mr. Brennan's expertise is unquestioned, and he has a close working relationship with the president. He's also on record (as of 2008) as opposed to waterboarding and other coercive tactics. On balance, that sounds pretty appealing. That said, we also need to hear from him about his views on the morality and legality of drone warfare, which has expanded markedly under Mr. Obama, and on the nation's detention policy for terrorism suspects.