On Feb. 6, in an historic expansion of international protection of terrorism suspects and other prisoners from being held in secret detention or being forced to disappear, 57 nations signed an international treaty in Paris.

This ban includes kidnapping (as in CIA “renditions” to countries known for torturing prisoners). The United States was invited to sign the treaty but refused despite our allowed adherence to the rule of law and our core emphasis on due process.

It would have been acutely embarrassing for the Bush administration to sign any assurances that we do not kidnap or otherwise “disappear” terrorism suspects. At this very moment, German prosecutors are pursing arrest warrants for 13 CIA agents charged with kidnapping a German citizen, Khaled el-Masri, and sending him to Afghanistan where he was sexually abused and beaten for five months.

Italian prosecutors have arrest warrants out for 25 CIA operatives charged with snatching Osama Moustafa Nasr off a street in Milan and sending him, shackled, to Egypt where he was subject to electric-shock interrogation and sexually abused. The chief of Italy’s military intelligence service, Nicolo Politari, has considered it necessary to resign for his alleged complicity with the CIA kidnappers.

For this constitutional republic to engage in these practices has made us lose the respect and confidence of many people around the world who do not hate the United States and, like us, are in justified fear of murderous terrorists.

What will it take to stop what an L.A. Times editorial called the “self-inflicted damage” of these renditions, which were started under President Clinton but expanded greatly by the current administration?

It will require a serious, not a grandstanding, congressional investigation — with subpoenas — of these “special powers” given to the CIA. From whom in the Justice Department, the Defense Department and the Oval Office have these authorizations and continuing cover-ups come from?

When the evidence has been gathered, the next necessary action by Congress must be to revise the Military Commissions Act of 2006, which immunized those involved with “renditions” from prosecution under our War Crimes Act of 1996.

On Jan. 18, at the start of a Senate Judiciary Hearing on Oversight of the Department of Justice, Sen. Patrick Leahy, its chairman, told Attorney General Alberto Gonzales: “The administration’s secret policies have ... reduced America’s standing around the world to one of the lowest points in our history.”

(Hentoff is a nationally syndicated columnist.)