North Carolina is one of only three states that grants driver's licenses without asking for a Social Security card or other proof of U.S. citizenship. This policy is supposed to encourage road safety and compel illegal immigrants to get car insurance. Whatever its merits, the policy made it easy for Mekki to get a license and a job. He even enrolled as a student at North Carolina Agricultural and Technical State University, where September 11 planner Khalid Shaikh Mohammed had studied in the 1980s.