As the chart above from Unions Work
shows, over the past nearly hundred years of American history, when union density has been low, inequality has been high. Union density isn't the only
factor in that, of course. But it's not a coincidence. Neither is this:
There are lots of complicated economic and political factors. But they tend to boil down to upward shifts in money and power, and workers getting squeezed. Even if you're not in a union, the fate of unions affects us all.