Manufacturing is largely non-union now BECAUSE of the excesses of industrial unions. And the remaining private-sector unions seem to be hell-bent on pricing their members out of the market.
No, remaining private sector unions have minimal advantage over their non-union counterparts. There are exceptions, however, such as the UAW, which enjoys a symbiotic relationship with management of the global automotive cartel. "Savings" generated by moving automotive component manufacturing offshore are never passed along to the consumer. The substandard conditions and wages exploited offshore merely support ludicrous bonuses for the entire cartel workforce, from the lowliest UAW janitor to the Ford and GM CEOs.