What's wrong with Islam?

Actually, the same thing that's wrong with Judaism and Christianity. It started with revelations from God, but was later overcome by intellectuals and philosophers. Moses, Jesus and Mohammed were all meek men who served God and their followers. None of them got rich or exercised great worldly power; their kingdoms were not of this world. Nor did their early followers. But once they were out of the way, the warriors and "scholars" took over and many of these were seduced by the power of being able to interpret revelations for the people. The Jews had an empire for a short while, but ended up losing their own land, not to regain it for 1900 years and are still without a tabernacle or temple.

Mohammed's war was defensive. Jesus was the prince of peace, but his promised second coming will be not so much a war as a violent cleansing of the world from all war. Moses's wars were commanded to destroy societies which had become so corrupt and evil (They sacrificed their infants to their idols) that their end had been decreed by God in order that they would not corrupt his people. They failed to obey that decree and ultimately lost their promised land and were forced to wander the rest of the world until their prophesied gathering commenced.

The golden age of Islam was during the Turkish rule. The Arabs never could overcome their own Bedouin heritage which kept them in a constant cycle of internecine war, except when they were dominated from without. Now they have been given freedom, but they realize that they have failed to keep up, or even to retain the advances made by the Ottomans. Since Islam was given by God and was supposed to fill the earth and hasn't, there were only two possible explanations: Its adherents were not worthy and therefore, not able, to complete the plan; or the religion as it has been interpreted by generations of taliban, mullahs, sheiks and ayatollahs is not true. Neither explanation is tolerable to Arab honor, so a third explanation has been posited: The West is Satan's system of opposing God's command and thus must be destroyed, even if it must be done with the weapons created in the West. This begs the question, why didn't God prevent the West from outstripping the Arabs in economic and military power, but that can't be acknowledged without the answer that Muslims have failed to be worthy of God's favor.

The existence of multiple variants of a religion is plain evidence that it is no longer in direct communication with God, for his house is a house of order. Therefore, some or all of the extant versions of the original revelation must be apostate to some degree. All three have gone through eras where they conquered others and established empires and became ultra wealthy. All three have gone through phases, or developed sects, of violence and inquisition. It seems to be Islam's turn at the moment.