What Is The Left's Back-Up Plan?

Will Wilkinson is wondering:

Supposing that Mr Walker and not the SEIU is the vanguard of historysupposing that America is headed toward the stable non-union equilibriumwhat is the next-best scenario from a progressive perspective? What is the answer if resurgent unionism is not? Is there one? I hear plenty of progressive rhetoric to the effect that only a rehabilitated union movement can save America from plutocracy and middle-class stagnation, but my sense is that this is a lot like conservative rhetoric to the effect that only a return to constitutional principles will save America from sclerotic socialist decline. Do progressives, like their conservative counterparts, really believe their own hype?

Steinglass thinks it a good question but doesn't have an answer.