Most American workers don't belong to unions.
Union participation across the nation dropped from 32 percent in the 1950s to 11.9 percent last year. Yet, union battles are as intense as ever, with local politicians calling out teachers' unions to Wisconsin Gov. Scott Walker's battle with state workers over a 2011 law limiting their right to enter into collective-bargaining agreements (photo, above). That law was overturned by a Wisconsin county judge in September -- with regard to city, county and school district workers -- but was left intact for state employees.