No place is safe. In an unprecedented bombing attack inside perhaps the most secure military base in Afghanistan killed two U.S. military personnel and two American civilians Friday. The blast Bagram Airbase north of Kabul came a day after a suicide bomber killed six at the German consulate in the northern city of Mazar-e-Sharif. The attack on the country’s largest base was claimed by a Taliban spokesman who said one of its fighters, posing as a laborer, attacked a sports facility. The blast also injured 16 other American GIs and a Polish soldier.