Why do union workers in WI say collective bargaining is a right when...?

in many states, public unions don't have it, and haven't had it? And... many of these states have Democrat Governors. Was the donation of $400 million to Obama from the unions a factor Obama is falsely accusing people denigrating union members when NO ONE is denigrating union member, maybe the calling out the 14 cowards who are still hiding in IL, but no one is bad mouthing the workers themselves.