That's because their both ultra-tribal, post-Christian religions. They both explicitely reject that the path to redemption is through personal faith in the ultimate sacrifice of the Son of God and instead make salvation dependant on legalistic hierarchies that they use to control their people. They're both fundamentally supremacist and would just as soon (or sooner) murder "infidels" as convert them.

You can call me naive but I still believe that something like a Liberal Democracy can exist and thrive but only within an explicitely Christian moral framework. Neither of these religions are compatible with the principles which built our countries in the West and allowing either to exist here is the political equivalent of you or I eating toxic waste.