This study is a year old, but I think it’s worth posting again. Chris Christie is fighting with the teachers unions. Verizon is fighting with the Communication Workers of America. I’ve always believed unions killed the US Steel industry.
Collective bargaining inhibits growth, and the less a state is impacted by unions, the better off its citizens will be.
Michigan is the worst affected state by unionism. South Carolina, which has been a right-to-work state for years, is affected the least. Compare the economies of those two states right now and the effect of unionism is clear.