Fatimids in Egypt

What has been is what will be, and what has been done is what will be done, and there is nothing new under the sun. (Ecclesiastes 1:9 ESV)

The following were taken from this website, "Fatimids in Egypt | History of Islam".

QUOTE
Islamic history is animated by a vision to establish a universal community enjoining what is right, forbidding what is wrong and believing in God. But there have been different interpretations of this vision. In the 10th century there were at least four different versions of that vision. The Fatimids based in North Africa claimed the Imamate in the lineage of Imam Ismail. The Karamatians were also Fatimids but were extremist in their views and believed that their version of Islam be imposed on all Muslims, by force if necessary. The Buyids were Twelvers who believed in the Imamate in the lineage of Imam Musa Kazim. Then there were the Sunnis, the vast majority of the population, who accepted the Caliphate in Baghdad. In the 10th century, these conflicting visions collided on the political military plane. And out of this confusion emerged the victorious Turks, displacing both the Caliphate and the Imamate by a new military-political institution - the Sultanate.

The excesses of the age gave birth to a revolution - the Murabitun revolution in Africa - and provoked the dialectic of Al Ghazzali, which altered the way Muslims looked upon Islam itself. Their internal rivalry denied the Muslims their last chance to conquer Europe. In the 9th and 10th centuries, Europe lived in the age of imagination, dominated by the talisman and ruled by feudal lords. After the death of Charlemagne in 814, his Carolingian heirs fought among themselves for the remnants of the Frankish kingdom. Faced with Viking attacks from the north, Europe could not defend itself in the south and was militarily vulnerable. The mutual hostility between the Fatimids, the Umayyads and the Abbasids prevented them from exploiting this historic window of opportunity. The Aghlabid conquest of Sicily and their raids into southern Italy as far as Rome in 846 marked the farthest advance of Muslims into southern Europe. The armies of the Fatimids, the Umayyads, the Buyids and the Abbasids spent their energies primarily at each other's throats.
UNQUOTE

What will happen if the Muslims today were able to conquer the world and impose Islam on the whole world? Exactly what happen in the past will happen again in the future. There will be fights on which interpretation of Islam is correct and you will have a corrupt Caliph enriching himself while pretending to impose morality on his people. Read the history of Islam for yourself. There is no example of Islam bringing progress to the people.

But Islam will never be able to conquer the Christians because God is always with the Christians. Just as God caused the Muslim to fight among themselves when the Christians were weak, so He will continue to preserve His people.