BAGHDAD (Reuters) - Iraq’s Popular Mobilization on Sunday called on the Iraqi government to ban U.S. nationals from entering Iraq and to expel those who are already in the country, in a reaction to the new U.S. travel curbs on Iraqis. Popular Mobilization is mainly a coalition of Shi’ite paramilitary groups armed and trained by Iran to fight Islamic State. It became an Iraqi government-approved body last year. The call to ban U.S. nationals came in a statement published by its spokesman, Ahmed al-Assadi. 