Dressed in a gray suit with an American flag pin in his lapel, then-Commerce Secretary Carlos Gutierrez said the modest two-lane span that U.S. taxpayers paid for would be "a critical transit route for trade and commerce" between Afghanistan and Tajikistan.

Today, the bridge across the muddy waters of the Panj River is carrying much more than vegetables and timber: It's paved the way for drug traffickers to transport larger loads of Afghan heroin and opium to Central Asia and beyond to Russia and Western Europe.

Standing near his truck in a dusty patch on the Afghan side of the river, Yar Mohammed said it was easy to drive drugs past the Afghan and Tajik border guards.

"It's an issue of money," said Mohammed, to the nods and grins of the small group of truckers gathered around him near the bridge at Nizhny Panj. "If you give them money, you can do whatever you want."