ISIL wants to kill all of those who have tried to kill and repress them and their families.  if it is true as you say that they want to kill the Pope, then it would be  because they see the Pope as some kind of ''leader''' of those who have / do oppress them.   Francis is a hero... a martyr.... a role model for all christians.   he has had his road to Emmaus and has reaped the benefits- for us.