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Propelloni parent
Yes, this will suck. No argument from me.

However, I disagree with your conception of Islam as a state, even if it was explained to you by Muslims. The strongest argument I can build from your statements is that, according to the reference to the end of the Sunni Caliphate in 1923,

p1) only Sunnis are Muslims, and

p2) the Caliphate is unique, and

p3) the Sunni Caliphate of 1923 is the original one, thus

c) it was the state of Islam.

We can disprove all of these premises. p1) is obvious, there are more Muslim religions than just Sunnis. The earliest schism was the Sunni-Shiites split, happening immediately after the first prophet's death.

About p2), while I'm fuzzy on the details, I'm pretty sure that between the 900s and the 1900s there were at least 3 major, parallel Caliphates and also a bunch of smaller Caliphates. Geographically they were even sometimes overlapping. It might be interesting that the Caliphate of the Ottoman Empire (the one in question) was a Hanafist (a Sunni splinter group) Caliphate.

On p3), the Sunni caliphate of 1923 was reestablished after a 300 year "hiatus" by the Ottoman Emperor to lay claim on Crimea. It had no representation besides a leader, the Sultan. Before the dissolution of the major Sunni Caliphate in the 1500s it relocated several times, from today's Syria to today's Iraq, to then and now Egypt. Thus we can say that the Caliphate had no continuous existence. We can furthermore say that the time the Sultan of the Ottoman Empire was the Caliph, it was because it was a diplomatic ploy of the secular power of the Ottoman Empire.

Therefore, c) must be wrong. There are more Muslims than Sunnis, the Sunni Caliphate wasn't unique, and the Caliphate that ended in 1923 was not the original one.

A less philosophical counter-argument could be the vigorous infighting between different Muslim groups we see today. I'm curious how the war on Iran changes that, if at all.