More inequality in America has come about because the middle class is harder to attain and has shrunk because the hard work of unskilled labor or even higher education are no longer adequate to break out of poverty into the middle class.
Unlike the previous generations, it now requires hard work and modern skills. This is the huge change in the American dream. My parents broke out of poverty from hard work alone, but the kids and the poor today are so frustrated because they were told hard work and an education was the ticket out and it's not. It now requires modern skills and a hard earned degree in sociology or law from Harvard and a lot of work ethic doesn't even cut it.
The people with modern skills are shooting right out of middle class and becoming wealthy because their skills are in such high demand. Business is screaming for more foreign workers because they have skills they can't get here.
We have to find a way to get the poor and the young and those with obsolete skills the technical skills needed to succeed in the modern world. It is the most important issue of our time because if you have no modern skills no matter how much education you have or safety nets, the American dream is dead.
It's not the rich get richer and the poor get poorer, it's the skilled (even the poor skilled foreigners) get richer and the U.S. poor have inadequate skills to break out. The only answer is to get business heavily involved in the U.S. education process. It's starting to happen and we need a lot more of it.