A bitter legacy of the Sept. 11, 2001, attacks on the United States is Russia’s heroin scourge that has spun out of control.

Opium production has increased 40 times since U.S.-led forces invaded Afghanistan in October 2001, a large percentage of which ends up in Russia, Federal Drug Control Service head Viktor Ivanov said. This has helped bring the number of Russia’s drug addicts to 2 million, causing 30,000 deaths a year.

In the beginning phases of the Afghan war, the Kremlin signed on to the idea that the U.S.-led campaign protected Russia’s security on its southern flank. This was why the Kremlin took the unprecedented decision to not object to the United States setting up military bases in Central Asia. This was the first time that U.S. and NATO forces were stationed in a former Soviet republic.

But by the late 2000s, the honeymoon in U.S.-Russian security cooperation had ended. The Kremlin went from the position that the United States was helping  beef up Russia’s security to arguing that it was undermining Russia’s security by not cracking down on Afghan drug traffickers.

Moderate Russian officials say the Americans are ignoring the narcotics problem in Afghanistan because they don’t want to lose the loyalty of their anti-Taliban allies. More conservative politicians and commentators claim that it is part of a U.S. conspiracy to weaken Russia by creating millions of drugged-out “zombies” in the crucial 18 to 30 age group.

In any event, it is clear that the United States is not treating the flow of Afghan narcotics into Russia seriously; after all, few of these drugs end up in the United States. This attitude needs to change.

There was an attempt to revive cooperation against Afghan drug trafficking to Russia last October, when the United States and Russia set up a joint operation to destroy laboratories producing heroin in the Nangarhar region of Afghanistan.

This cooperation needs to continue.

The United States has a moral responsibility to help Russia and the former Soviet republics in Central Asia control the flow of drugs from Afghanistan, and this should continue long after U.S. forces leave in 2014. Washington should throw its support behind the idea of combining a permanent contingent of NATO and Collective Security Treaty Organization forces to help close the holes in the borders between Afghanistan, Uzbekistan and Tajikistan. It should also continue raids against heroin plantations and fund infrastructure projects to help Afghans find employment that is not related to narcotics.

This would one of the best ways to return to the spirit of cooperation that Russia showed to the United States after the 9/11 attacks. Russia is facing its own deadly invasion— an uncontrollable flow of drugs from Afghanistan — and needs the full support of the United States to help fight this battle.