I know I'm repeating a comment made earlier, but I still think that there is a perception that unions have gone from insisting on appropriate wages and benefits to protecting workers who clearly should be fired and imposing ridiculous work rules
and you are correct. Even more important is the perception that union leadership is more interested in playing politics on the national stage then they are in doing their day jobs, and that they fund this sideline with union dues. You see this in the way they run our pension programs too, where they use the money to fund projects based upon a whole lot of other factors that come before return on investment or the likelihood that money lent by the pension will ever be seen again. The union bosses by and large don't care about what they claim to care about, and they live very well of of our union dues while returning very little of value to the rank and file. Picking fights with management and working to keep every no good bum on the payroll is intended to make it seem like they are doing something for us, but all of the non idiots see through this pretty quickly, as union efforts are not in either the workers or the companies best interest.
But all this does not explain why a third of the population would rather end unions then try to fix them. All this does not explain why new unions did not start up to take over from the old corrupt ones, new unions that could have very easily chosen to do the work that unions were designed to do, that the workers presumably would want them to do.
Something else is going on here.....