Don't kid yourself. We all know it's implying that they are all on some sort of "equal footing".
Islamic terrorist have been at the top of the charts for terrorism forever. This isn't one of those topics where we just stop at "well every religion has it's terrorist", because we know that Islam has more issues with creating terrorist than ANY other religion by far.
You need a doctrine or belief of some sorts in order to commit something in the name of it.
Atheist don't believe there is a god, they are not convinced a god exist or any religion is true. That's it.