You really have to be ignorant of US history not to realize the importance of the labor movement. By the way, since the all-out attack on unions started, real income of American middle and lower-class workers has declined at a steady rate. If it hadn't been the ready availability of easy credit, our standard of living would have plummeted. Now that the bill's coming due you're going to see very clearly what damage anti-union policies have done.
Unfortunately, my history classes rarely made it to the 20th century, and it might have been 1 class session, if that. I would have loved to know more about the 20th century. FYI, yes, I went to public schools. The sad part is that I haven't done much to fill that gap in my knowledge besides watching the History channel. I do see value in labor unions, but I probably don't have the historical knowledge to fully appreciate their role in history.