15 years after 9/11, national security is stronger -- but so are the threats

As we approach the 15th anniversary of 9/11, we ponder the question: Is America safer now from terrorism than it was on that fateful day? Steven Brill spent the last year evaluating what has changed, including tightened airline security policies, but also how the country returned to "politics as usual." He speaks with Judy Woodruff about his findings -- and his recommendations.