I believe it is more of a "cult" - at least in my opinion, based on what definitions I could find. Any time one is forced to belong, it is different from religion, where as one "joins" - per se'.Muslim is a religion by any definition.
Many minimize the cult reality by calling it other names, such as the religion of hate.
What I find interesting, people have no difficulty calling christian extremists as cults.
We have been giving the cult of islam a pass for centuries. I am their enemy, I am a christian and they want to kill me. What other "religion" can you name that wants me dead?
Call it what it is - an evil cult.