It is a symptom of the denial and willful ignorance that blankets the present age that this book even had to be written, and that Ibn Warraq, a historian and social theorist of preeminent insight and wisdom, should have had to devote his considerable talents to it.

Nonetheless, we can be grateful that he has given us The Islam in Islamic Terrorism: The Importance of Beliefs, Ideas, and Ideology, as this book is breathtakingly comprehensive despite its quite manageable length, and is, quite simply, irrefutable. If there remains in the world anyone who holds that Islam is a Religion of Peace and yet has sufficient intellectual honesty and acumen to consider these arguments on their merits, this is the book to give.

First there is the necessary work of clearing away the nonsense. Ibn Warraq takes up each of the major excuses that are commonly given for Islamic jihad violence — that it is all about Israel, or all about U.S. foreign policy, or all about poverty and lack of opportunity — and shows why each does not and cannot sufficiently explain the phenomenon at hand.

Then he treads ground that has been much-tilled before: the exhortations to jihad violence in the Qur’an and Sunnah. But here, even the most well-informed reader will find much that is new, especially the detailed description of the Islamic concept of al-walaa wal baraa, commanding the right and forbidding the wrong, and how it leads to jihad attacks against unbelievers.

Also highly rewarding is Warraq’s examination of a subject that receives insufficient attention: the goals of jihad. Authorities in Europe and North America continue to treat jihad attacks as discrete criminal acts that have no necessary connection to any wider movement or imperative. Ibn Warraq shows here, with copious references to Islamic scholars ancient and modern, that jihad is a means of spreading Islam, and that the “greater jihad” — the spiritualized idea so beloved of Western apologists — actually has quite slim foundation in the Islamic sources, and is given scant attention throughout Islamic history by the religion’s foremost theologians.

The most rewarding sections of this amply rewarding book are Ibn Warraq’s surveys of jihad in theory and practice from the death of Muhammad up to the present day.

This includes a look at the Kharijites, who are often invoked by contemporary Islamic apologists as the precursors of modern terrorists and the archetypal Islamic heretics. Ibn Warraq, by contrast, demonstrates that “the fundamental principle for the Kharijites was that the Islamic community must be based on the Koran.” Those who claim the Kharijites were twisting and hijacking Islam say the same thing about contemporary jihadis, with just as little justification.

The historical survey that makes up the balance of the book is its most illuminating and valuable material. While many informed readers will know that the Qur’an exhorts jihad and that Muhammad preached and practiced it, few will be familiar with the history of jihad violence in ninth and tenth century Baghdad, or with the Qadizadeli movement in 17th century Constantinople, or with the career of Ibn Abd al-Wahhab (of Wahhabi fame) and his movement.

This is jihad doctrine as applied by Muslims throughout history. Readers will see immediately that Muslim obedience to the exhortations to jihad warfare in the Qur’an and Sunnah has been remarkably consistent in form since the beginnings of Islam.

Those who would peruse this material and then still insist that Ibn Warraq is “cherry picking” from both Islamic scripture and history, leaving out both the peaceful exhortations and the fabled eras of peace and tolerance, would be willfully and incurably blind. There are no such exhortations of any force, and no such eras, as any serious student of renowned al-Andalus will know.

The facts are, in the final analysis, quite simple: the Qur’an teaches jihad warfare. So does Muhammad. So do the mainstream Islamic theologians and jurists. And Muslims have consequently waged jihad warfare throughout history.

The Islam in Islamic Terrorism offers facts that ought to be taught in every high school and college history class; a saner age than ours would not find this book remotely controversial. It may indeed have mandated that it be put to exactly that kind of use in academic institutions.

As it is, this book will most likely not be used in schools, which will continue to purvey the half-truths and outright lies that pass for scholarly exposition of Islam these days. The students will not be the only ones who lose out. Among the losers also will be those whose lives will be taken when they otherwise could have been spared were it not for all the willful ignorance that prevents an honest evaluation of the threat we face.

Ibn Warraq has performed an immense service in The Islam in Islamic Terrorism. Anyone who wonders, and has the courage to brave the opprobrium of our self-appointed moral superiors to find out, will get the truth in this invaluable and deftly executed book.