America at 250: New poll finds nation divided over its identity and future

With celebrations for the nation's 250th anniversary well underway, the country's mood can be summed up as complicated, according to a new PBS News/NPR/Marist poll. Most Americans say the nation has drifted from its founding ideals, and a growing number believe violence may be necessary to set the country on the right path. Liz Landers has insights from the poll and its respondents.