Private sector unions will continue to shrink in size and importance as long as their public sector counterparts make union activities look bad. When unionized public sector union leaders refuse to consider any cuts in pay and benefits no matter how badly they're bankrupting gummints at all levels, people will look at all unions as simply greedy and not distiguish between the private versus public situation.

Too bad that the tar brush is so broad, but until private sector union leaders start distancing themselves from their public sector brothers and sisters, that's inevitable.