If Americans ever think about the employees of government subcontractors, it’s doubtful that sex traders, indentured servants and exploited workers living in barbed-wire compounds come to mind.

They should now.

That’s the image left by a congressional hearing Wednesday that asked: “Are government contractors exploiting workers overseas?”

The answer apparently is yes. What’s also disturbing about this story is Uncle Sam’s ineptness in stopping the exploitation.

Although sad, this story isn’t new. In fact, much of the discussion at the House Oversight and Government Reform subcommittee hearing was based on journalistic accounts. The headlines of two articles sum up the situation: “U.S. policy a paper tiger against sex trade in war zones” was the title of a June 2010 Washington Post article by Nick Schwellenbach and Carol Leonnig. “For foreign workers on U.S. bases in Iraq and Afghanistan, war can be hell,” a New Yorker piece by Sarah Stillman said a year later.

The workers, Stillman wrote, “primarily from South Asia and Africa, often live in barbed-wire compounds on U.S. bases, eat at meagre chow halls. . . . A large number are employed by fly-by-night subcontractors who are financed by the American taxpayer but who often operate outside the law. . . . Many of them recount having been robbed of wages, injured without compensation, subjected to sexual assault, and held in conditions resembling indentured servitude by their subcontractor bosses.”

No one knows how many tax-funded though poorly paid workers are in such conditions, but estimates at the hearing were in the tens of thousands.

“Estimates vary considerably on the scale of human trafficking, but whatever the number of victims is, the problem is serious,” Schwellenbach testified. “The U.S. has been a global leader in combating trafficking in persons, yet our tax dollars are inadvertently fueling this human rights tragedy through our labor supply chain in war zones and other contingency operations.” Schwellenbach worked with The Post as a staff writer for the Center for Public Integrity, and he appeared before the panel in his current role as investigations director for the Project on Government Oversight.

The U.S. leadership role he mentioned seems to exist more in theory than practice, if the testimony at the hearing is any indication. Rep. James Lankford (R-Okla.), chairman of the subcommittee on technology, information policy, intergovernmental relations and procurement reform, noted the government’s zero-tolerance policy for human trafficking but said that “yet these stories continue to rise up.”

He presided over the meeting in a room off a back corridor of the Rayburn House Office Building. The session drew no high-ranking officials and little media attention. Only a few representatives were there, and they didn’t appear to like what they heard.

“Human trafficking by federal overseas contractors is widespread and never punished,” said Rep. Gerald E. Connolly (Va.), the top Democrat on the panel. “Not a single case of human trafficking, sexual assault, wage theft or related crimes has been prosecuted by the Department of Justice, and only a single case has even been referred for prosecution by the Department of Defense. . . . Neither the Army and Air Force Exchange Service nor any other component of DoD or the State Department has suspended or debarred a single federal contractor for human trafficking, even though such abuses are routine.”

One good thing that emerged from the hearing was the sight of Republicans and Democrats united in outrage at how American tax dollars are at work exploiting people. The subcommittee told agency officials to submit, by Feb. 1, recommendations to prevent abusive labor practices by contractors. In a joint statement, Lankford and Connolly said the subcommittee would hold further hearings on the issue.

“These labor practices violate every human value that we have as a country,” Lankford said after the hearing. “Our departments of State and Defense stand up and fight for human rights around the globe, but have turned a blind eye to these foreign workers. We believe that all men and women are created equal, and the United States must not stand idly by as these injustices occur on a daily basis under our nose.”

Those values are outlined in various federal polices, rules and regulations listed by government witnesses. But all that paper apparently doesn’t mean much. Testimony by the Congressional Research Service lists anti-trafficking laws, regulations, official guidance, presidential directive, agency instructions, treaties, United Nations protocol, international conventions and an employee “bill of rights” developed by the Army and Air Force Exchange Service, which operates stores, restaurants and beauty parlors on military bases.

Yet, human trafficking continues.

The research service recognizes that the policies it listed aren’t getting the job done. Speaking for the research service, Liana Wyler, an international crime analyst with the agency, suggested that Congress might want to explore “whether there is a disconnect between existing policies and their implementation among contractors overseas.”

The hearing left little doubt that there is.

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