A U.S. marine has been killed in northern Iraq. The Pentagon said Staff Sgt. Louis Cardin was killed Saturday by enemy rocket fire near Makhmur. He was 27. His death appears to have revealed the existence of a new U.S. fire base in Iraq where CNN reports hundreds of marines have been living in tents. Cardin is the second U.S. servicemember killed since the U.S. campaign against ISIL began in 2014.