NAFISA ELTAHIR and HUMEYRA PAMUK THE United States has reinstated Sudan's sovereign immunity, as the U.S. Congress passed legislation formalizing the move, following the ending of Sudan's designation as a state sponsor of terror. However, the legislation includes an exemption allowing lawsuits by the families of victims of the September 11, 2001, attacks on the United States already underway in U.S. courts to move forward, although experts say Sudan is unlikely to lose those cases. The state sponsor of terror designation, which was in place for almost three decades, had weighed on Sudan's economy and restricted its ability to receive…