I realize that this is but another view of Salmo's post, but I found it interesting that this author attaches some causation and possibly implied blame for the topic of our discussion. I found his claimed cause of "Technology and competition from abroad whittling away at blue collar jobs and pay" to be believable and of particular interest, especially in light of the time frame that is shown in the graph.
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60 Years of American Economic History, Told in 1 Graph
Jordan Weissmann Aug 23 2012, 3:17 PM ET


In the 60 years after World War II, the United States built the world's greatest middle class economy, then unbuilt it. And if you want a single snapshot that captures the broad sweep of that transformation, you could do much worse than this graph from a new Pew report, which tracks how average family incomes have changed at each rung of the economic ladder from 1950 through 2010.

Here's the arc it captures: In the immediate postwar period, America's rapid growth favored the middle and lower classes. The poorest fifth of all households, in fact, fared best. Then, in the 1970s, amid two oil crises and awful inflation, things ground to a halt. The country backed off the postwar, center-left consensus -- captured by Richard Nixon's comment that "we're all Keynesians now" -- and tried Reaganism instead. We cut taxes. Technology and competition from abroad started whittling away at blue collar jobs and pay. The financial markets took off. And so when growth returned, it favored the investment class -- the top 20 percent, and especially the top 5 percent (and, though it's not on this chart, the top 1 percent more than anybody).



And then it all fell apart. The aughts were a lost decade for families, and it's not clear how much better they'll fare in the next.

None of this is new history.But it's helpful to have a crisp layout of what's changed.
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Please note that the big drop in mean family income starts in the 1970 to 1980 segment of the graph. Now have you ever heard of Malcom McLean? He invented the shipping container in 1956 and by the end of the 1960s, Sea-Land Industries had 27,000 trailer-type containers, 36 trailer ships and access to over 30 port cities. The ability to securely and cheaply move products anywhere in the world most certainly gave the technology and competition from abroad a chance to start whittling away at blue collar jobs and was surely a nail in the coffin of the blue collar worker.

I realize that the adaptation of containerized shipping is but one part of a complex situation, however it is an important part. And we should all realize that all change brings displacement and opportunity.