when we gathered all of the data in 9/11 program to be fair, jim, congress then limited access to mettia data in the foreign intelligence surveillance act but it was not constitutionally limited. it was limited by statute. and after 9/11, using authority for chief authorities decide that had to the agree to stop from doing that, the statute had to be unconstitutional because defendant limiting his inherent article tool, that stood up, has that constitutional authority. >> after words airs on book tv every saturday at 10:00 p.m. and sunday at 9:00 p.m. eastern. you can watch all previous after words programs on our website, booktv.org. >> and now on book tv, new jersey senator corey booker discusses civic involvement and recounts the experience that shaped political thinking, he discusses his book united with robert george of the new york post >> you'd drop a book called united, why the title and why now? >> well, first of all, it's great to be here. [laughter] >> it's actually nice to be on it. >> exactly. >> and i appreciate you being here and not making me feel in anyway challenged. [laught