Conservatives have been saying that the National Labor Relations Board’s complaint against The Boeing Co. is about right to work—specifically about a company in a non-right-to-work state setting up an assembly line in a right-to-work state. Earlier this week I heard an interesting take on that from the font of right-to-work himself, Mark Mix.

First, a definition. “Right to work” is about the union shop, in which employees represented by a union must pay union dues to keep their jobs. In a “right to work” state a union shop is banned. Unions can organize a group of private-sector workers by petitioning for a vote, and if the union wins the vote it will represent everyone in the group. That’s the same in all states. But in a right-to-work state the union cannot make everyone in the group it represents pay dues. Dues remain voluntary. In a non-right-to-work state, dues may be voluntary and may not, depending on the labor contract.

Twenty-two states, mostly the “red” states politically, are right-to-work states. In the West, Idaho is a right-to-work state. So are Nevada, Utah and Arizona. Washington is not, nor are Alaska, Oregon or California. South Carolina—the state involved in the Labor Board’s case against Boeing—is a right-to-work state.

Back to Mark Mix. He is president of the National Right to Work Committee, in Springfield, Va. The committee tries to convince states to become, and remain, right-to-work states—which is opposite of what the union movement does. Unions stand up for the right of workers to join unions. Mix’s committee stands up for the right of workers not to join unions, or to have to pay dues to them. In Mix’s terminology, Washington is a forced-unionism state.

All of which makes the two sides enemies.

Anyway, Mix was here to attend the opening hearing of the Labor Board’s case against Boeing. The opening statement of the administrative law judge was that Boeing and the International Association of Machinists and Aerospace Workers should make peace, and settle the IAM’s complaint without going through the Labor Board process. The interesting point is why Mix is afraid of that.

Mix is afraid that any settlement will involve Boeing agreeing to card-check in South Carolina and at any other nonunion locations, which would set a precedent in labor that the right-to-work people would not like.

Another definition. Card check is a proposal that a group of workers could create a labor union by open ballot instead of secret ballot. Under card-check, an organizer could buttonhole each worker, outside the place of work, at his home, or any other place, hand him a pledge card and ask him to sign it. If the union could get signed cards from a majority of the workers in the group, it would represent the whole group, the same as if it had won a secret-ballot election.

The labor movement likes card-check as a way of bypassing what it considers employer coercion. The right-to-work people oppose it because it creates opportunities for coercion by labor organizers. During the Bush administration, the Democrats in the House of Representatives passed out a federal card-check bill, only to have it die in the Senate. Many expected card-check to zip through the Democratic Congress elected in 2008, but it did not—thanks partly to the Mark Mix and his organization.

What Mix fears is that by and by the federal government—a Democratic administration—will lean on Boeing. An official in Washington, D.C., will call Boeing and say, “You have all these federal contracts—the tanker, for example—and we’d like you to pay serious attention to what the union wants.”

Thus pressured, Boeing will cut a deal agreeing to card check. And in its South Carolina plant, where the employees have already voted out the IAM, Boeing might well win a card-check fight, Mix says. Other employers will not be so fortunate.

The importance of the deal Mix imagines would be that card check “becomes the new standard for cases in which the union alleges retaliation,” he says. “This would be card check by administrative decree.”

And that, to Mix, would be much more consequential to American industry than the question of whether Boeing can assemble 787s in South Carolina.