if the sources used in this piece are primarily accurate this is a very comprehensive group of articles, based upon our history and current economic factors, which bring to our attention the current fact of a grown and growing inequality of incomes in this country and thus the shrinking of the middle class, which, if it follows what has happened before in other countries, may place our democracy in jeopardy.

This opinion piece has minimal journalistic value. The author has not read basic economics. If he had he would know that you NEVER, EVER compare income percentiles from year to year. You study how individuals in one income range in one year do in a later year. People in the lowest 20% income range in 1996 gained 90% by 2005 (the latest year range for which the IRS has done the detailed comparisons); people in the top 5% and top 1% in 1996 had LESS income in 2005, and most had dropped out of the range. Badly researched.

Makes assumptions to prove his hypotheses that are unrealistic, "But when economists look at actual labor markets" but what he really looks at are geographical locations and markets segregated into unrelated categories.

Excellent article ... so far (there are apparently more parts to this story to come). But the article has already dispelled many of the purported causes of the "wealth divide" and shown others to have too little effect to be a primary cause. I'm looking forward to reading the primary causes (and especially the supporting data) for this divide. The comparison of wealth divisions in the US compared with other democracies in the world is also eye-opening.