Until the advent of materialism and 19th c. dogma, Western Civilisation was superior to anything Islam had developed. Islam has not aided in the development of the modern world; in fact civilisation has only been created in spite of Islam. Proof of this resides in the 'modern' world and the unending political-economic and spiritual poverty of Muslim states and regions. Squatting on richer civilisations is not 'progress'. Islam is pagan, totalitarian, and irrational.
The Moslem Caliphate is aspiration to empire. It is a state both physical and metaphysical of Moslem superiority over the hated non-Moslem, the apes, pigs, and slaves of the Koran. ISIS now firmly in control over large swathes of Syria and Iraq have issued a Caliphate passport at the bottom of which is written: “[If] holder of the passport [is] harmed, we will deploy armies for his service.” If you harm a Caliphate 'citizen' the totalitarian Jihad of Islam will kill you.
Historically a Caliphate is premised upon totalitarian Sharia, the worst anti-human, contra-free will fascism in history. Sharia is not 'law' it is the opposite – a bronze-age barbarism that was better left in the Arabian deserts. Moslem Sharia-mandated barbarity includes stoning, cutting off of hands and feet for theft; dishonor killing of young girls and wives; and much to the titillation of Western Atheists and secularists; the destruction of Christian crosses, churches, houses, and an extraction of the humiliating jizya, as per Koran 9:29, in which non-Moslems are looted to pay for the Moslem state and the cult of Moslem males which run it. Islam is very hiearchical. Moslem Arab males dominate and the rest of humanity cascades below this 'supreme race' until one reaches Blacks, Jews and slave girls.
The grandiose Caliphate par excellence is expressed by the totalitarian diktat of the mighty Arab conqueror of much of the Near East, one Umar Ibn al-Khattab (d. 644) who was the 2nd 'rightly guided' Caliph. Umar's dictatorship which lasted barely a decade [a little shorter than the Third Reich but just as busy, 634-644], witnessed the Moslem evisceration and domination of Christian civilization in Syria, Iraq and Egypt. Surely ISIS and other Moslem fanatics today would love to recreate a la Nasser, a new Caliphate in the same lands ?
Umar's regime, like all other implementation of totalitarian fascism, was premised on extortion, control, and the dehumanizing of the 'other'. Von Kremer, the 19th century German scholar of Islam, described the Caliphate's “central idea” as being the furtherance of “…the religious-military development of Islam at the expense of the conquered nations.” So it was. He wrote this in 1868. Since then our collective intelligence towards the inherent fascist theology of Islam has only waned. So much for the 'evolution' of the species. Umar's reign was an expression of hardship for non-Moslems including harsh inequality, intolerance, and injustice. These verifiable historical facts were observed by von Kremer in the mid-19th century and they are still very much with us today.
Umar's numerous and savage jihad campaigns waged were entirely consistent with the then nascent and developing Sharia or as some term it 'Islamic Law'. The Moslems under Umar spared neither Christian cities nor their monasteries if they resisted in any way, the predations of their Moslem masters. When the Byzantine- Greek garrison of Gaza refused to submit and convert to Islam, every single man was put to death. So much for the vaunted Moslem tolerance we hear so much about. In the year 640, hundreds of Greek soldiers who refused to apostatize became martyrs, and between 638-640 hundreds of thousands of Christians in Caesarea, Tripolis and Tyre, newly conquered by the Moslems, converted to the cult of Sin [Hub'al the Moon deity of Mecca] out of fear for their life. Apparently the Moslem erasure of the Gazan garrison had made an impression.
Al-Tabari a Moslem-Arab historian and much lauded by Moslemophiles as one of the great sages in history, recorded with a grinning happy style, the annihilation of 'Infidels' at Basrah in Iraq in 636 AD quoting Umar and his version of the Koran.
“Summon the people to God; those who respond to your call, accept it from them, but those who refuse must pay the poll tax out of humiliation and lowliness. (Koran 9:29) If they refuse this, it is the sword without leniency. Fear God with regard to what you have been entrusted.”
The 'Caliphate' was a one-way system of 'toleration'. Non-Moslems were forced to 'accept' Islam or second-class knave status. Moslems had no obligations whatsoever, outside of rape, looting and taxing, to the non-Moslem untermensch. It has always been thus with Islam.