Why is this recession so deep, and what can be done to reverse it?

Hint: Go back about 50 years, when America's middle class was expanding and the economy was soaring. Paychecks were big enough to allow us to buy all the goods and services we produced. It was a virtuous circle. Good pay meant more purchases, and more purchases meant more jobs.

At the center of this virtuous circle were unions. In 1955, more than a third of working Americans belonged to one. Unions gave them the bargaining leverage they needed to get the paychecks that kept the economy going. So many Americans were unionized that wage agreements spilled over to nonunionized workplaces as well. Employers knew they had to match union wages to compete for workers and to recruit the best ones.