And our good friends the Russians and Chinese are working hard to cut that supply line:
The SCO (Shanghai Cooperation Organization. consisting of Russia, China, Kazakhstan, Tajikistan, Uzbekistan and Kyrgyzstan) held several days of joint military exercises in Kyrgyzstan. These were largely to improve cooperation between the troops of the nations, in the event that the larger partners (Russia and China) were called in to help with a counter-terrorism operation, or to help keep a local ruler in power. At the moment, the major goals of the SCO is to get the United States to withdraw their troops and bases from the region. Russia and China, which dominate the organization, believe American influence is threatening the dictators who dominate the governments of Central Asia.
Yet another reason to to detroy the mullah regime in Iran and put in a friendly government bolstered by democracy. We need a more secure supply line to Afghanistan.
For those who think the only real war is in Afghanistan, the road to Kabul may go through Tehran, quite literally.