There are plenty of knowledgeable observers who confirm that the likes of ISIS are indeed Islamic. But there are also plenty of Islam apologists, especially on the Left, who claim they have "nothing to do with Islam", that they have "hijacked the religion of peace" and so on.
Now we have Al-Azhar university in Cairo affirming that ISIS are indeed Islamic. Al-Azhat is the oldest and most authoritative university in the Islamic world. It's pronouncement (a fatwa) should be the last word on the subject. Murderers who shout "Allahu Akbar" as they go about their bloody business are genuine Muslims.
Or is Al-Azhar islamophobic? Kidding. So what does a Leftie do?