Writing a book about ISIS without inadvertently promoting ISIS

I’m writing a book about ISIS (the terrorist organization.)

At the same time that I want people to read and be educated about ISIS, I also don’t want to give ISIS what could essentially be free publicity and advertisement. I’m depicting ISIS as brutal, extremely violent and ruthless and a major threat, of course, but for terrorists, any attention - good or bad - can work to advance their cause.
How do you raise awareness about a terrorist organization without inadvertently promoting it?