that's the topic of our signature segment tonight, special correspondent jeff greenfield reports. >>eporter: this was the american cityscape when television was new: forests of rooftop antennas, capturing signals over the air from a half-dozen channels that fought for space on a crowded broadcast spectrum. turning those signals into flickering, sometimes ghostly black and white images on small screens. for almost 90% of today's homes, television comes to us through cable or telephone wires or via satellite. our cable bills bring us a so- called "bundle" of more than 900 channels. but most of us watch an average of only 17. and now, more and more viewers, unwilling to pay ever-higher fees for a huge "bundle" of choices they rarely use, are turning to a new technology that may threaten the very foundation of the cable tv industry. over the past five years, 3.8 million american homes have "cut the cord," canceling or refusing cable. younger viewers, so-called" millennials" form a growing class of "cord-nevers," rejecting the cost of a monthly cable bill, they've turned instead to broadb

joining me to discuss this is jeff greenfield. jeff it's about proportionality here and the tone of the coverage but this notion of airplane crashes being somehow in a category all their own, interested in your thoughts on that. >> yeah i think it is the same example where people will tell you that when a plane lands, the pilot will say you just finished the safest part of your journey, be careful on the drive home. statistically, it's much more dangerous to be in a car than airplane but what happens i think, to the all of us when you hear about a plane crash is the absolute loss of control. the absolute certainty of which you're doomed. you can survive a car accident. it gets and creates a picture in our mind. we're there, parts of us are there lying dead on a mountain top. anybody on a plane can understand what that feels like. and it's like any other kind of story where a sudden horrible thought enters your mind, post 9/11 is an example. you can picture yourself in that situation and it sort of remains with powerful force, and i

jeff greenfield, a journalist that is done cnn, abc cbs.he was the editor then of the cargo at the university of wisconsin. so i had never heard political debate. i was from a family that was very engaged in the community but it was a civic duty. i had no sense of partisanship. i didn't know the difference between republicans and democrats, and almost failed a sophomore english exam on dickens because i didn't know the difference between republicans and democrats. that's changed. >> so here you were at this national convention 1000 people, student body president newspaper editors it seemed tremendously exciting. and then her husband got an invitation. what was about? >> the following spring one of the officers from nsa visited us and talked to him and invited him to apply for something called the international student relations seminar. it was going to be held the coming summer in 65 in pennsylvania. the innocent office at that point, headquarters, was in philadelphia. this was just outside. he applied and was accepted, and we had a tiny ba