The crisis in Iraq is a flashing warning light about the dangers of a reductionist national security policy that sends a signal of weakness to friends and enemies abroad. The most immediate crisis is in Mesopotamia. But we can be sure that the Taliban in Afghanistan are watching closely to see if the withdrawal of American forces comes to mean American indifference. Beyond the Hindu Kush, east across the Zagros Mountains and to the north of Iraq, hard-eyed men in Beijing. Tehran and Moscow are also calculating the implications of our handling of this crisis. The stakes could not be higher.