Hoda Muthana with her son in Syria. Ms. Muthana was a 20-year-old college student in Alabama when she joined the Islamic State in 2014. She used Twitter to encourage terrorist attacks in the West, but now says she regrets it and wants to return to the United States.Credit...Ivor Prickett for The New York Times AL HAWL CAMP, Syria — She was a 20-year-old college student in Alabama who had become co