We have been labouring under the lie that there is an “Islamic system” far too long; that there is some sort of comprehensive governmental model that provides the solutions to every imaginable social ill; and this is utterly fraudulent and profoundly destructive.
There is no system. There are rules (and they are not many), and any system that implements those rules, or even aspires to do so, is by definition “Islamic”.
When you base your political ambitions on the notion that you have to establish an “Islamic system”, you are unavoidably calling for the destruction of whatever system currently exists so you can supplant it with your own model. That would be dangerous enough even if you actually HAVE a model, but when you don’t, it is nothing but a call to destruction.
And no, the existence in Islamic history of various models of government does not translate to the existence of any particularly mandated governmental model. Those were simply the systems they were able to come up with at the time; no more no less. And just as they were free to develop models to address the circumstances and conditions of the time, so are we.