There is a skunk at the picnic.

Labor Day used to be the end-of-summer holiday celebrating the dignity and value of honest labor. But today's labor leaders have turned their backs on that all-American, patriotic holiday. They think it's all about politics.

America's labor movement has strayed a long way from its original mission. Take, for example, the attempt by local union officials in Wausau, Wis., to exclude Republican participation in a Labor Day parade. Such shenanigans illustrate how today's labor leaders are more interested in playing partisan politics than they are in the bread-and-butter issues of jobs and wages.

Nowhere is this sad development more obvious – and odious – than the unions' position on immigration. If there is one force in American politics that should be fighting for immigration control, it is organized labor. Decades of mass immigration have eroded wages and working conditions for millions of American working people. Especially in the construction trades, hospitality and tourism, millions of jobs now held by illegal aliens were once held by working-class Americans.

The gradual erosion of organized labor's historic position on immigration came to a climax in 2000, a presidential election year, when the AFL-CIO abandoned its traditional stance and signed on to the open-borders agenda. The union pledged its support for increased immigration and lax enforcement of existing immigration laws. It is probably no coincidence that this happened at the same time the Service Employees International Union (SEIU), the union that recruits illegal workers in the hotel and restaurant industry, began flexing its political muscle.

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All of this certainly would have come as quite a shock to AFL founder Samuel Gompers. Widely regarded as the father of the modern American labor movement, Gompers' career as a labor leader coincided with the so-called Second Great Wave of immigration from 1880-1920. Though himself an immigrant, Gompers well understood the dangers that mass immigration posed to American workers, and he lobbied tirelessly for restricted immigration.

In a letter to Congress in 1924, Gompers identified two "hostile forces of considerable strength" that opposed halting immigration. "One of these is composed of corporation employers who desire to employ physical strength (broad backs) at the lowest possible wage and who prefer a rapidly revolving labor supply at low wages to a regular supply of American wage earners at fair wages," he wrote. "The other," Gompers continued, "is composed of racial groups in the United States who oppose all restrictive legislation because they want the doors left open for an influx of their countrymen regardless of the menace to the people of their adopted country."

In reading these words, we are struck by how little has changed. Today, as in 1924, there exists an unholy alliance between Big Business hungry for cheap labor and ethnic lobbyists like the National Council of La Raza eager to expand their power and influence. What has changed is the conduct of the labor unions. The impact of the unholy alliance (and the unions' indifference) on American working people is evident in the town of Wausau, Wis., itself.

In a 1994, Roy Beck wrote in the Atlantic Monthly about how immigration had transformed Wausau. The town was a peaceful community, but all of that changed in the late-1970s when Southeast Asian refugees began settling in Wausau. The trickle of newcomers soon became a steady stream, and before long the town was beset with all of the problems mass immigration typically brings: overcrowded schools, high rates of welfare dependency, increased crime and gang activity, and the emergence of social and racial tensions.

In countless cities across America, over the past decade organized labor threw in the towel and welcomed illegal workers into membership. Some will say this was a rational accommodation to the undeniable fact that the federal government is not enforcing its laws against unlawful employment. As illegal workers displaced legal ones across dozens of blue-collar occupations, labor unions simply adjusted to the new reality and signed up the illegal workers.

To a local labor leader, say, of the carpenters' union in Denver or Buffalo, it's only sensible to agree with the maxim: if you can't beat them, join them. If they pay dues, who cares if they displace other workers? The fight was lost at the national level, so local union leaders see no downside to harvesting the fruit of that political sellout.

Yet, this Labor Day, it's worth remembering that Wausau story. It is the story of countless cities and towns throughout the country, from Waukegan to Waco, Tucson to Tacoma. It might well have been a very different story if American labor leaders had remained true to the principles of Samuel Gompers and put the economic interests of working people above ideology. But to today's labor leaders, it's more important to keep Republicans out of their parades.