It started during the Cold War, in the 1950s, when the Americans ran a secret base in Peshawar from which Gary Powers, the pilot of a U-2 spy plane, took off before being shot down over the Soviet Union in 1960. The two countries forged a momentous partnership in the 1980s to expel the Soviets from Afghanistan, declaring victory in 1989. But barely a year later Washington slapped painful sanctions on Pakistan over its covert nuclear weapons programme. Stung, the Pakistanis
