A lot has happened over the past 30 years, but if you're looking for a single political sea change that's had the biggest impact on middle class wages—more important than union decline, more important than NAFTA, more important than the end of Glass-Steagall—it's the political consensus that underlies the Fed's reluctance to allow labor markets to stay tight enough to generate wage increases in the real economy. And it's something we're seeing all over again right now, as the DC chattering classes have almost unanimously decided that inflation is our real enemy right now, even though core inflation is running around 1% and unemployment is still near 9%.

This is a policy beloved of the business community, which prefers loose labor markets that keep wages low and executive compensation high, but it hasn't always been the Fed's policy and it's not written in stone that it has to be now. Tight labor markets and rising middle-class wages are, to a large extent, a choice we make. Politics took them away 30 years ago, and politics can return them to us if we want.