As I usually do, let me drop a pull quote or two - different from Robb's - to whet your appetite to go and read the whole thing.
Measured by money, things look relatively grim for the American middle class and the poor. Men’s inflation-adjusted average wages peaked in 1973, and inflation-adjusted household incomes for much of the middle class have shown little or no growth in some time. The incomes of those at the top of the distribution (which is not composed of a stable group of individuals, political rhetoric notwithstanding) continue to pull away from those in the middle and those at the bottom. The difference between a CEO’s compensation and the average worker’s compensation continues to grow.Williamson starts his piece with a wonderful parable involving second graders trading SweeTarts for Gummie Worms and their socialist teacher. If you have time to read those few paragraphs, it's worth it as well.
But much of that is written into the code. If, for example, you measure inequality by comparing the number of dollars it takes to land at a certain income percentile, with a hard floor on the low end (that being $0.00 per year in wages) but no ceiling on the top end, and if you have growth in the economy, then it is a mathematical inevitability that incomes at the top will continue to pull away from incomes at the bottom, for the same reason that any point on the surface of a balloon will get farther and farther away from the imaginary fixed point at its center as the balloon is inflated. This will be the case whether you have the public policies of Singapore or Sweden, and indeed it is the case in both Singapore and Sweden.
Purely symbolic systems are easy to manipulate, which is why any two economists can take the same set of well-documented economic data and derive from it diametrically opposed conclusions.