Starting in January 2017, John Brennan became one of President Trump's most blunt critics among former national security professionals. In the years since, he has been working on writing a book, now available, called "Undaunted: My Fight Against America's Enemies at Home and Abroad." David Priess sat down with John to talk about the book and his career. They talked about what brought him to the CIA, his career as a CIA officer and manager, his work overseas at the CIA, his time at the White House as the Deputy Assistant to the President for Homeland Security and Counterterrorism for President Obama in his first term, and his time as CIA director in President Obama's second term. They covered some controversies, including enhanced interrogation, the reorganization of the CIA in the so-called modernization effort, Russian interference in the 2016 election, and of course, his outspoken criticisms of the president ever since.