The U.N. report revealed deeply disturbing detainee abuse in a war-torn nation. It detailed "systemic torture" of the worst kind, including beatings, electric shocks, threatened sexual assaults and forced confessions.

Similar barbarism in Mideast nations during the Arab Spring had prompted U.S. action in the region. Responses ranged from nudging ostensible ally Bahrain to curtail its security forces, to imploring the U.N. Security Council to impose robust sanctions against Syria, to joining a NATO coalition to militarily aid rebels fighting to oust Libyan leader Moammar Gadhafi.

But the abuse reported this week was not the product of one of those rogue regimes. Rather, it was linked to Afghan President Hamid Karzai's corrupt government, which we have propped up through a decade of war that's cost the lives of countless Afghans, about 1,800 U.S. service members and billions of U.S. dollars.

The report does not conclude whether U.S. officials were aware of the torture or whether they acted upon the scant verifiable information that may have been produced by the abuse. But now that the report has been issued, it's imperative that every effort be made to prevent the abuse from happening again.

It's encouraging that some steps have already been taken, including halting transfers of alleged insurgents to the Afghan prisons where detainees were tortured. And the report suggests that some top Afghan officials cooperated in the fact-finding and have begun to try to fix the system.

Those who perpetrated the torture need to be identified and prosecuted. And Afghan security forces must be trained to recognize that torturing detainees is not only morally and legally wrong, but also counterproductive. It's an ineffective tool to extract intelligence, and it backfires as a punitive measure. Insurgents fearing that they will be tortured if captured have greater incentive to fight to the death, putting U.S. forces in even more danger.

Our forces are already beginning a slow drawdown in Afghanistan. They are likely to leave without a clear-cut victory, as there is no immediate military solution to this war. Rather, the best hope for peace is through some kind of negotiated process. But this will be even more difficult if the Karzai government is further delegitimized by human-rights abuses.

The report could trigger the so-called Leahy amendment, which states that neither the U.S. State nor Defense Departments can continue to give assistance or training to any security service unit if there is evidence of gross human-rights abuses. The U.N. report makes it clear that such evidence exists.

While there are legitimate legal reasons to walk away from yet another dysfunctional element of Karzai's government, cutting off funding and training for Afghan security personnel now would be counterproductive. We are not outside observers in Afghanistan. We are inextricably linked to the Afghan government, military and police forces, and reform must remain a U.S. priority. Unfortunately, this will only be accomplished if the United States actively addresses the security system failures until Afghan detainees are treated in accordance with American values, not those we routinely, and rightly, criticize elsewhere in the region.