Actually, the most successful union organizing in American history came when the state temporarily took control of the national economy in WWII and more or less required firms with government contracts (all the ones that mattered) to allow unions to organize. But the romantic myth of the glorious battles of the thirties works so much better than the dull realities of the benefits of state corporatism in the forties.
"The issue is not unity with other leftists per se but unity of the working class-- while one may at times serve the other, they are not inevitably linked. Folks who denounce working with Democrats really don't have much credibility in suddenly discussing the wonders of unity-- it's all so selective rhetoric that it's hard to take too seriously."
And since over 90% of the private-sector working class is no longer represented by unions, should we "unite" with the vast majority of them in a union-free environment? For that matter, who here has ever denounced "working with Democrats"? Every leftist organizer, including the Sparts, the WWP, the RCP, DAN, the Chicago Surrealists, the IWW - all of them "work with" Democrats. We all know that "working with Democrats" is necessary; but some of us don't think it's sufficient.