Here's an article pinpointing when things went wrong in America. (I've been saying this for years). He says what went wrong, but not how it happened. He says it's because our values changed. Yes, that's what happened. But why? What made them change? There's lots of comments on the site, if you like that sort of thing.
Find it here: http://www.eoionline.org/blog/x-marks-the-spot-where-inequality-took-root-dig-here/#comment-32554