As the US-led kinetic war against ISIS continues with indifferent success and less than certain prospects to date, answering the obvious question of what motivates that murderous organization becomes more pressing by the day. Remarkably, there have been no visible efforts in that direction by either the White House or the Defense Department. Indeed, the much touted Obama Administration-sponsored conference on “countering violent extremism” further obfuscated the issue by its oxymoronic definition of terrorism as “acts of violence” committed “against people of different faiths, by people of different faiths.” Neither did the “Team America” high-level Pentagon-sponsored recent meeting in Kuwait help much with its lapidary conclusion that the US strategy against ISIS is correct.

Against that meager analytical background, a much discussed and praised effort to decipher ISIS ideology by journalist Graeme Wood in the March issue of the Atlantic Magazine deserves close scrutiny, because it is a good example of just how muddled and unrealistic our understanding of radical Islam with respect to ISIS has become.

Titled “What Does ISIS Really Want,” the article’s main contribution is its common sense proposition that ISIS is Islamic, indeed, “very Islamic.” Unfortunately, the rest of it is a largely failed effort to explain what drives ISIS to do what it does with a confused exegesis of its Islamic beliefs and interviews with several sympathizers. Key emphasis is given to its ostensible eschatological predilections as a “key agent of the coming apocalypse” and a “headline player in the imminent end of the world” when the messiah Mahdi will show up on Judgment Day. Mr. Wood also makes much of ISIS’s reported faithfulness to something called the “prophetic methodology of the caliphate” and implies strongly that what they practice is a “distinctive variety” and a “coherent and even learned interpretation of Islam,” which aims “returning civilization to a seventh century legal environment.”

Much of this makes little sense to anybody who’s familiar with the foundational texts of Islam. It is true that the Quran does deal with Judgment Day in Sura 75 (Yawm al-Qiyamah), but much of what it says appears to be borrowed from the Bible and Mahdi, an essentially Shia concept, is not mentioned at all. ‘Prophetic methodology’ is a propaganda term used by ISIS and means nothing, especially in connection with the caliphate, which is not mentioned in either the Quran or the traditions (Sunna) of Muhammad. As far as the “seventh century legal environment” is concerned, it’s worth noting that during Muhammad’s life time and that of his immediate successors, there was no Islamic corpus juris in existence and to the extent that a legal system existed at all, it was mostly the old Arab customary law (urf) and arbitration that were practiced. In fact, the codification of sharia as Islamic law did not begin until the middle of the 8^th century and was not completed until the end of the 9^th century, or 2^nd and 3^rd century of Islam.

If ISIS ideology thus has little to do with “prophetic methodology” and eschatological propaganda, it has everything to do with sharia.  And the reason for that is very simple, for sharia is the most radical possible interpretation of Islam and a real source of legitimacy for those practicing it among the millions of Islamist sympathizers.

So what exactly is sharia? To radical Islamists, salafis and jihadists of all kinds, sharia is ‘God’s sacred law’ to be obeyed to the letter if a Muslim were to end up in heaven. More than that, it is also the constitution of the Islamic state and the guarantee of the perfect synergy between religion and the state (din wa dawla). To reform-minded Muslims and most non-Muslims it is nothing of the kind. Rather it is a post-Quranic, man-made doctrine designed to legitimate the imperialist policies of the hereditary Muslim empires that followed Muhammad and his successors and the open discrimination against non-Muslims and women widely practiced by them. Moreover, sharia was based for the most part not on the Quran, but on secondary and often unreliable sources such as the hadith (Muhammad’s sayings).

To the extent that sharia is based on the Quran, the cornerstone of its interpretation is the doctrine of abrogation (naskh), which invalidates most of the peaceful and tolerant verses of the earlier Meccan period and replaces them with the later violence-preaching Medinese verses.  As a result, sharia is not only radical and intolerant, but is also in direct conflict with many Quranic injunctions. Thus, the punishment for apostasy is death in sharia, but 100 lashes in the Quran. The former makes the establishment of the caliphate and sharia a religious obligation for Muslims, while the latter does not mention either one of them at all. In the Quran, Muslims are enjoined to fight in self-defense, sharia makes offensive jihad for the spread of Islam mandatory among many other examples.  If one were to characterize sharia today, which Muslims have been obligated to follow blindly (taqlid) since the 10^th century, what comes readily to mind is the Catholic faith at the time of the inquisition.

The discriminatory and violent nature of sharia’s injunctions made it impractical as a law early on in Muslim states that were multi-national and multi-confessional, as most of them were, and though it was regularly paid lip service to, it was seldom practiced, except occasionally as family law. In the early Muslim empires, for instance, justice was administered mostly by courts of grievance (mazalim), police courts (shurta) or market judges (sahib al souk), rather than sharia, while in the historically greatest Muslim state of all, the Ottoman empire, the law of the land was kanun osmanly, an essentially secular law.

In fact, sharia’s political fortunes did not change for the better until the patron saints of contemporary radical Islam, Abul ala Mawdudi and Sayyid Qutb, elevated the imposition of sharia as the sole criterion of whether or not a state is Muslim or apostate in middle of the 20^th century. Since then, with the help of huge amounts of Saudi money and the spread of Muslim Brotherhood networks, sharia has become the sine qua non of the radical Islamist idiom that currently dominates the Muslim establishment worldwide. It is simply a fact that from the Organization of the Islamic Conference (OIC) on down to countless mosques, Islamic centers and Muslim organizations, no rule, regulation or bylaw is viewed as legitimate if it contradicts sharia.

What the widespread support for sharia among Muslims means is that President Obama’s repeatedly expressed belief that there is no radical Islam, but just individual terrorists, is widely off the mark. In just a couple of examples relevant to ISIS, a recent open letter signed by 126 prominent Muslims from around the world, including many US Islamists, denouncing ISIS’ tactics, nonetheless endorses sharia. In another example, a radical Wahhabi preacher and passionate sharia supporter named Mohamed al-Arefe, approved of raping kidnapped Yazidi women in a tweet to his 10 million followers, while the prominent Islamist and member of the influential “senior council  of clerics” in Saudi Arabia, Saleh al-Fawzan, issued a fatwa arguing that whoever denies the legitimacy of slavery in sharia becomes an infidel.

For jihadist organizations like ISIS, being sharia-compliant in a self-proclaimed caliphate bestows them huge legitimacy in the eyes of the devout. What we view as barbaric practices, including raping and enslaving “infidel” women, crucifixions, killing homosexuals and Muslim apostates, are fully justified in sharia. Undoubtedly, the ISIS cutthroats believe that some of their more recent gruesome innovations, such as chopping off women’s hands for using cell phones or beheading smokers, are also legitimate under sharia.

Muslims are also obligated by sharia to emigrate to the caliphate, which helps explain the huge number of volunteer jihadists who continue to flock to ISIS. The ISIS’ self-anointed  “Caliph Ibrahim” enjoys yet another political benefit under sharia, which orders Muslims to obey him even if he is “unjust,” because  “a rebellion against a caliph is one of the greatest enormities.”

What is beyond doubt is sharia’s absolute incompatibility with basic human rights, democratic norms and the law of nations and its highly seditious nature in calling for violence against non-Muslims and non-conforming Muslims both. Until the community of nations and the Muslims themselves come to terms with this malignant doctrine and act to delegitimize it, its poisonous offshoots like ISIS will continue to thrive.

Alex Alexiev is a senior fellow with the International Assessment and Strategy Center (IASC) in Wash. D.C. and chairman of the Center for Balkan and Black Sea Studies (cbbss.org) in Sofia, Bulgaria. His latest book on Islamism "The Wages of Extremism: Radical Islam's Threat to the West and the Muslim World," is available as a pdf file from the Hudson Institute.