domestic intelligence as much as it is about policing. say something about that. >> spies and subversives have been the fbi's target 100 years ago. it's been the main mission. this creates a conflict, a tug-of-war. we all want to be safe and we all want to be free. the fbi has to wake up every day and counteract that balance. >> it's about domestic stuff that aren't so comfortable. >> these are secret service intelligence missions against people who want to blow up the united states or oppose the president of the united states. >> j. edgar hoover plays i huge role in your book. i want to put up a quote you have in the beginning of your book of how to think about him. his loyalists saw him as a visionary genius, his opponents saw him as a sewer in the words of president kennedy's national security as adviser.