The relationship between the United States and Pakistan has fluctuated between tenuous cooperation and rampant discord. During the Cold War, Washington strengthened ties with Islamabad, doling out more than $3 billion in aid to Pakistan to arm the mujahideen fighting the Soviets in Afghanistan. After a period of relative inactivity between the nations during the 1990s, the 9/11 attacks prompted Washington to reinvigorate ties with Islamabad once again. On Monday, the current state of the relationship between the two nations was put to the test when U.S. President Barack Obama announced that a drone strike in Pakistan's Balochistan province killed the leader of the Taliban, Mullah Akhtar Mansoor. The strike comes at a precarious moment for bilateral ties between the United States and Pakistan. Last week, the U.S. House of Representatives passed an amendment to the National Defense Authorization Act that would block $450 million in funding to Pakistan.