You absolutely have to distinguish between Islam and Islamism, just like people need to distinguish between Zionism and simply being Jewish. Or for that matter between the various forms of Christianity and their levels of political involvement.
People have a right to religious beliefs. They do not - must not - have the right to turn that into a legal enforcement of those beliefs on people who do not share them.
It's a totalitarian ideology which is fundamentally opposed to liberal democracy. It shouldn't be tolerated for the same reasons Nazism shouldn't be tolerated.
People have a right to religious beliefs. They do not - must not - have the right to turn that into a legal enforcement of those beliefs on people who do not share them.