As far as President Obama was concerned, the issue was crystal clear: Republicans in Michigan were about to strip workers there of their rights by passing a right-to-work law.

"What we shouldn't be doing is trying to take away your rights to bargain for better wages and working conditions," he said at a campaign-style appearance at the Daimler Detroit Diesel plant in Redford, Mich., on Monday. "We shouldn't be doing that. These so-called right-to-work laws, they don't have to do with economics; they have everything to do with politics. What they're really talking about is giving you the right to work for less money," he said.

Like most critics of right-to-work laws, he avoided describing what the laws specifically do. You'd never know from listening to him that the laws do nothing to take away the right to collectively bargain. Or that they give workers a powerful way to ensure that unions are really representing their best interests.

The bottom line is this: The laws give workers the right to decide not to join a union or to pay dues to one if they don't want to. That's it. What the president and his allies in Big Labor are arguing for is the union's right to coerce people into supporting a union financially.

Here's how it works: Most states operate under "closed shop" rules. That means a union can negotiate contracts with employers that include the requirement that the employer can only hire people who belong to or pay dues to a union. The legal theory here is that since the union's collective bargaining benefits all workers, all should be required to pay the union.

Of course, that gives the worker no say in the matter.

As of last week, 23 states had right-to-work laws, meaning workers are allowed to opt out of both union membership and dues payments. In April, when the law signed Tuesday goes into effect, Michigan will become the 24th, and the second Rust Belt state to adopt it, following Indiana earlier this year.

The widely held political presumption regarding right-to-work laws is that they will result in mass attrition of union membership as people take advantage of them to drop out. That's the not-so-veiled reason the Right favors them and the Left hates them.

For example, after Wisconsin Gov. Scott Walker, a Republican, allowed public employees to opt out of unions, the state branch of the American Federation of State, County and Municipal Employees lost 45 percent of it members in the first month, according to the Wall Street Journal. The AFSCME has disputed the figure but has not given an alternate number. Each of the state's largest teachers unions lost 30 percent of its members.

Still, there is little other hard data on how right-to-work legislation affects union membership. Most right-to-work states adopted such legislation before 1960 and lacked a strong labor history to begin with.

The results are still coming in from Indiana, but Oklahoma provides an interesting test case. When Oklahoma was debating the law in 2000, according to, the state had a private-sector unionization rate of 4.4 percent. In 2011, the rate was 3.8 percent. So there has been a decline of 14 percent, but that's actually slower than private-sector unions' national decline of 23 percent during the same period.

Jimmy Curry, president of the Oklahoma AFL-CIO, told me earlier this year that he was able to adjust to right-to-work legislation with only minor losses. Labor law experts note that right-to-work forces unions to be more attentive to their members' needs to keep them on board.

Some workers in Michigan could use that -- especially the ones hired by General Motors after the federal bailout. The United Auto Workers had to make at least some concessions at the time, so they opted to mainly protect incumbent workers by hitting the new ones with dramatic pay cuts. Under this two-tiered wage system, new workers earn about half what the

older ones get. They get fewer benefits too, without any hope of graduating to the higher tier or its compensation schedule. And, of course, they get to pay dues to the union that did this to them. Not much of a deal.

Now those new workers will have a chance to hold their union to account.

Sean Higgins ( is a senior editorial writer for The Washington Examiner. Follow him on Twitter at @seanghiggins.