The dissident unions of the AFL-CIO are meeting in Washington today to announce that they are building a halfway house.

The Change to Win Coalition -- and boy, is that ever a provisional-sounding and utterly clunky name -- will begin life neither entirely within nor without the AFL-CIO. One of its founders, the Service Employees International Union (SEIU), the AFL-CIO's largest affiliate, passed a resolution last weekend authorizing its top officers to take the union out of the federation when they deem it appropriate. All signs indicate that will happen soon.

The other founders -- the Teamsters, the food and commercial workers (both million-member unions), UNITE-HERE (the apparel and hotel workers union) and the laborers -- have each (well, all but the laborers) made noises about decamping from the federation unless more money is devoted to organizing and incumbent President John Sweeney is replaced at the AFL-CIO's July convention.

But Sweeney and his allies command a clear majority of the federation's unions, and they insist that all the dissidents except SEIU are bluffing. The food and commercial workers need the help of the AFL-CIO to organize Wal-Mart, they argue; UNITE-HERE cannot risk the withdrawal of massive union deposits from Amalgamated Bank (the nation's one labor bank, which UNITE-HERE owns).

For their part, the dissidents insist that the price of a Sweeney victory may be the dissolution of a unified labor movement. "Sweeney loses by winning," says one dissident leader. "He can win the vote at the AFL-CIO convention, but so what? It's a voluntary organization. We can leave."

In a sense, the leaders of American labor -- people who have spent their lives at the bargaining tables -- are engaging one another in a massive game of chicken. But such games can take on a life of their own, with all manner of unforeseen consequences. The Change to Win Coalition may begin as a modest group devoted to coordinating some joint organizing efforts by its member unions. But if those efforts grow, so will the financial demands on its members, which will then find themselves paying dues to both a full-fledged federation, so long as they stay in the AFL-CIO, and a new group that could look more and more like a federation rival. Under those circumstances, predicts the dissident leader, "We're not going to pay double dues."

If nothing else, today's declaration ensures that the federation's coming convention -- originally conceived as a celebration of the 50th anniversary of the merger of the AFL and the CIO -- will be a bitter affair. It was never wholly clear what there was to celebrate: At the time of the 1955 merger, 35 percent of the U.S. workforce was unionized; today that figure stands at just 12.5 percent. Unions are surely not the primary authors of their own demise, but to the extent that they are responsible, their decline can be traced back to a fateful error made at the time of the merger.

Fifty years ago CIO (and United Auto Workers) President Walter Reuther argued that the newly merged federation should be charged with organizing those sectors of the economy and regions of the country where labor had little or no presence. George Meany, then president of the AFL, countered that the individual affiliates should have that responsibility, and it was Meany's position that prevailed. Over the decades, however, most unions stuck to meeting the needs of their existing members. At first, secure in their existing labor markets, they considered the tasks of organizing the Sunbelt and the new economy beneath them. In time, with their own sectors shriveled and with the how-tos of organizing all but forgotten, they realized that such tasks were beyond them.

The seven or eight of the 57 unions in the federation that can and do organize are found on each side of the current divide; what separates them most are their differing assessments of whether the 71-year-old Sweeney, who has served as AFL-CIO president for the past decade, can make the kind of changes needed to reverse labor's decline. The SEIU is right in its initial contention that the movement must be restructured so it can organize again. (Merging unions that lack organizing capacity is hardly a sufficient condition for new growth, but it's a necessary one.)

But Sweeney's defenders are probably right, too, in arguing that splitting the movement would fragment the force required to organize Wal-Mart or dethrone Tom DeLay in 2006. "This is a movement based on concerted action," one federation staffer says. "Unity is the most practical operating principle we have."

But not today in Washington, where the new watchword of American labor has become, "Workers of the world, divide."