Sen. Hillary Clinton of New York is set to speak to a group of Michigan labor leaders Saturday, as part of the AFL-CIO’s get-to-know-the-candidates exercise. (It’s the series which prompted Sen. Joe Biden to accidentally undercut his own support of the hilariously misnamed “Employee Free Choice Act”.) But Sen. Clinton is facing a different kind of labor issue right now: union bosses are mad that one of her advisors runs a company which helps employers explain themselves to employees. Don’t get the problem? We’ll explain.

Mark Penn is Clinton’s top political advisor, as well as the CEO of Burson-Marsteller. That company helps some employers deal with their employees and educate them about the very real risks of joining a union. Shouldn’t be controversial, except that any criticism sends union bosses into a rage (as we’ve learned firsthand at the Center for Union Facts). The AFL-CIO’s John Sweeney and SEIU’s Andy Stern are just the latest to weigh in.

The Nation reports that, despite a statement from Penn saying he doesn’t personally work on union issues with employers, union bosses want him to shut down any such work by the company:

Yet some labor officials hoped Penn would go much further, taking steps toward terminating B-M’s “labor relations” division or at least ending the contract with Cintas. Neither will occur, nor is Penn taking a formal leave of absence from the company. He’s also not distancing himself from the money the “labor relations” wing brings in and the other controversial clients B-M represents in the defense, pharmaceutical and energy industries and the Republican lobbyists he oversees.

The Nationistas even conclude that Penn’s reasonable statement is only “a phony gesture that fails to address the underlying problems or the reasons prominent labor leaders are upset with Clinton’s campaign.” As union bosses would apparently have it, the only sincere gesture is to shut up and toe the line.