US withdrawal of military support during 1965, 1971, and 1975 led to a widespread perception in Pakistan that the US was an unreliable ally and had betrayed Pakistan. Initially, their relations were cordial but later on, this alliance became weaker especially during Zulfiqar Ali Bhutto's government. Bhutto after taking charge of the government reshaped Pakistan's internal and external politics. He adopted new dimensions regarding Pakistan's Foreign policy goals. He tried to free Pakistan from US influence and dependence and desired Pakistan to acquire nuclear capabilities. The paper aims to throw light on the factors that led to the drift in Pak-US relations. The findings of the study concluded that Bhutto adopted socialist policies and promoted friendly relations with socialist countries like the Soviet Union and the Peoples' Republic of China. All these steps were against the US interests. Pakistan also abandoned SEATO and CENTO pacts during this phase.