Afghanistan and the United States have signed a strategic partnership agreement. This agreement gives the U.S. continued access to the bases it uses in Afghanistan, and lays out the rules under which American troops operate in the country. Meanwhile, Afghan troops arrested members of a drug gang and seized five tons of opium. The government has been careful with the drug gangs, because many of them formed partnerships with tribes, especially pro-Taliban tribes. This has increased tension between Afghan and American officials. Cracking down on the drug producing tribes will result in more angry tribesmen, causing more of the kind of fighting that has cursed Afghanistan for centuries. But the United States, and most of the rest of the world (including neighboring Iran and Pakistan) want the Afghan heroin and opium production much reduced. Iran and Pakistan are having a growing problem with cheap drugs, and drug addiction.