author yoni applebaum focuses on that dilemma in his new book "stuck." we talked to him tonight. start, let's get our terms right, what is the mobility crisis or the challenge in mobility that america faces right now? >> we talk a lot about an affordable housing crisis. housing is too expensive. in places americans most want to live. it's really cheap in other parts of the country. the problem is we've got a mismatch, a mobility crisis. people can't do what they've done for 200 years in america. they can't leave the places with fewer opportunities and choose to go to the places that have more opportunities. >> john: is it possible to distinguish those who move and those who don't? >> this is another reversal. for a long time, the people who moved in america were those seeking a better life for themselves. increasingly, moving in america has become a privilege of the affluent and the educated. the americans who most need the kinds of opportunities that new locations could give them have become the least likely to be able to relocate there. >> john: why have we come to this pass? >