This chart, from a book by Branko Milanovic via Carpe Diem reinforces a point about income distribution I make all the time - for all we talk about income distribution in this country, our poorest 20% would be middle class in many countries of the world. While I would love to see our poor doing even better, it begs the question of whether distribution or absolute prosperity is more important.
Just to give you a feel for reading the chart, the US's lowest ventile, or bottom 5%, have income that would put them in the 68th percentile worldwide. Our poorest 20% (the first 4 ventiles) would be upper middle class or better in Brazil, China, and India.
When comparing to European social democracies, it turns out that while the US's income distribution is wider, that is almost entirely due to the top end being higher. The poorest 10% make about the same as the poorest 10% in Europe, and I would argue that this analysis (from a leftish think tank) actually underestimates a quality of life advantage for American poor, who come out higher even than the middle class in Europe on things like living space and appliance ownership.