> Meanwhile, for those who have been around long enough to have a sense for the 'barometric' changes he's talking about -- the shift in the basic, underlying "we're-all-in-this-together" ethos has been not just noticeable, but profound. Probably a lot more work needs to be done to find a solid statistical basis behind this observation (if this is at all possible).

I need to see some very solid evidence before I change my assumption, which is that people have always felt this as they get older, because we romanticize our memories of youth and we are uncomfortable with the societal changes that younger generations inevitably introduce.