The State Department has approved a proposed $4.5 billion sale of four Boeing [BA] KC-46A Pegasus tankers and associated equipment to Qatar, which could become the fourth nation after the U.S., Japan, and Israel to operate the Pegasus. The State Department announcement provided no explanation why the price that the Qataris would pay for the equipment is so high, given that KC-46As have a unit cost of about $250 million. Defense Daily will add any State Department explanation received. In…