The Wisconsin budget reforms DO NOT take away someone's right to join a union. They simply require a union to use a method other than collective bargaining to negotiate benefits for government workers. Government employees can still collectively bargain wages.
Also, unions are not required by law to provide the same benefits to non-union members they do union members. They actually reject the option to negotiate only for members and fight to put non-members into their agreements so they can use the "we have to take care of freeloaders" argument in future negotiations.
If a union boss' lips are moving, he's lying.