How do Americans view organized labor this Labor Day?

According to Gallop, support for labor unions is at a historic low. There has been a sharp decline in the last year.



Powerline Blog suggests reasons for this decline.

What seems odd about these poll data is their volatility. Both Gallup and Rasmussen find support for unions down sharply from a year ago. Why would someone favor unions last year but disapprove of them this year? Maybe it has to do with card check or the bailouts, or, more broadly, people being reminded of how union bosses behave when they're in power.