PAK-US RELATION SINCE 2001 Introduction : In spite of this type of collaboration and mutual interests, the relationships between the Pakistan and U.S in the war against the terror did not remain without the resistances. Debatably, the Pak-U.S relationships, since the war against terror had launched, stayed burdened with bitterness and captive to the firmness of Washington on Islamabad with the demand to do more to eliminate the network of terrorists forces, Al-Qaida and Taliban, apparently operational from the tribal regions of Pakistan and committing terrorism related activities around the border areas. Furthermore, the recurrent use of drone strikes by U.S in Federally Administered Tribal Areas of Pakistan, pressure of Washington on Islamabad to be decisive in opposition to the network of Dr. Qadeer Khan for its participation in propagation of nuclear programs and deal regarding nuclear system between India and U.S are the main fundamental reasons of the disagreement between Pa