How can a fundamentally weak Muslim world be a threat to an economically and militarily superior West?
One of the least explored answers to this conundrum revolves around an antithesis – namely, how the West portrays Islam today, compared to its actual historic experiences with Islam.
In fact, from Islam's first contact with Western civilization and for more than a millennium thereafter, Muslims behaved not unlike the Islamic State and on the same conviction: that Islam commands war on – and the enslavement or slaughter of – non-Muslims.
During this perennial jihad that began in the seventh century, almost three-quarters of Christendom's original territory – including all of North Africa, Egypt, Greater Syria and Anatolia – was permanently swallowed up by Islam.
European nations and territories that were attacked and/or came under Muslim occupation (sometimes for centuries) include: Portugal, Spain, France, Italy, Iceland, Denmark, England, Sicily, Switzerland, Austria, Hungary, Greece, Russia, Poland, Bulgaria, Ukraine, Lithuania, Romania, Albania, Serbia, Armenia, Georgia, Crete, Cyprus, Bosnia-Herzegovina, Macedonia, Belarus, Malta and Sardinia.
Between the 15th and 18th centuries alone, approximately five million Europeans were abducted and enslaved in the name of jihad. (Exactly how many were kidnapped during the great Arab slave raids on Europe between the poorly documented eighth and 11th centuries is unknown.)
The largest Islamic army ever to invade European territory – some 200,000 martyrdom-seeking jihadis – came as late as 1683 to conquer Vienna but failed.
But even as the Ottoman Empire was beginning its slow retreat from eastern Europe, the Muslim slavers of the so-called Barbary States of North Africa wreaked havoc all along the coasts of Europe – reaching even Iceland. The United States of America's first war – which it fought before it could even elect its first president – was against these Islamic slavers. When Thomas Jefferson and John Adams asked Barbary's ambassador why his countrymen were enslaving American sailors, the "ambassador answered us that it was founded on the laws of their Prophet, that it was written in their Koran, that... it was their right and duty to make war upon them [non-Muslims] wherever they could be found, and to make slaves of all they could take as prisoners..."
In short, for well over a millennium – punctuated by a Crusader-rebuttal about which the modern West is obsessed – Islam posed an existential threat to Western civilization (as copiously documented in my new book, Sword and Scimitar: Fourteen Centuries of War between Islam and the West).
After writing, "For almost a thousand years, from the first Moorish landing in Spain  to the second Turkish siege of Vienna , Europe was under constant threat from Islam," Bernard Lewis elaborates: "All but the easternmost provinces of the Islamic realm had been taken from Christian rulers... North Africa, Egypt, Syria, even Persian-ruled Iraq, had been Christian countries, in which Christianity was older and more deeply rooted than in most of Europe.
Their loss was sorely felt and heightened the fear that a similar fate was in store for Europe," as wave after wave of Islamic attacks crashed against the continent.
Yet no sooner did Europe neutralize Islam that it forgot all about its ancient antagonist. As historian Hilaire Belloc (b. 1870) observed during the peak of Western might and Muslim weakness:
"Millions of modern people of the white civilization – that is, the civilization of Europe and America – have forgotten all about Islam. They have never come in contact with it. They take for granted that it is decaying, and that, anyway, it is just a foreign religion which will not concern them. It is, as a fact, the most formidable and persistent enemy which our civilization has had, and may at any moment become as large a menace in the future as it has been in the past."
But worse than just "forgetting," the West has rewritten history to fit its postmodern paradigms. Today, whether as taught in high school or college, whether as portrayed by Hollywood or the news media, the predominant historic narrative is that Muslims are the historic victims of intolerant Western Christians (as I was once informed during a televised interview).
Even otherwise objective history books contribute to this distorted thinking. They talk of "Arab," "Moorish," "Ottoman," or "Tatar" – rarely Islamic – invasions, without mentioning that the selfsame rationale – jihad – impelled those otherwise diverse peoples to assault the West.
But all this is history, it might be argued. Why rehash it? Why not let it be and move on, begin a new chapter of mutual tolerance and respect, even if history must be "touched up" a bit?
This would be a somewhat plausible position if not for the fact that, all around the globe, many Muslims are still exhibiting the same imperial impulse and intolerant supremacism of their forbears (reportedly 215 million Christians are currently experiencing "high levels of persecution," mostly in the Muslim world; others are experiencing a genocide in the name of jihad.)
None of this should be surprising: in classrooms all across the Islamic world, Muslim children are taught to glorify the jihadi conquests of yore – while despising infidels. Thus, while the progressive West demonizes European/Christian history – when I was in elementary school, Christopher Columbus was a hero, when I reached college, he became a villain – Mehmet the Conqueror, a pedophile whose atrocities against eastern Europe make the Islamic State appear tame, is praised every year in "secular" Turkey on the anniversary of the savage sack Constantinople.
It is often said that those who ignore history are destined to repeat it. What does one say of those who rewrite history in a way that demonizes their ancestors while whitewashing the crimes of their persecutors?
The result is before us. The history recounted in Sword and Scimitar is not repeating itself; sword waving Muslims are not forcing their way into Europe. Rather, various Western European nations are opening their doors to and lying prostrate before Islamic aggression. In Germany and the United Kingdom, crime and rape have soared in direct proportion to the number of Muslim refugees accepted. Sweden alone – where rape has increased by 1,472% since that country embraced "multiculturalism" – is reportedly on the verge of collapse.
In the future (whatever one there may be) the histories written about our times will likely stress how our era, ironically called the "information age," was not an age when people were so well informed, but rather an age when disinformation was so widespread and unquestioned that generations of people lived in bubbles of alternate realities – until they were finally popped.
Raymond Ibrahim, author of Sword and Scimitar: Fourteen Centuries of War between Islam and the West, is a Judith Rosen Friedman fellow at the Middle East Forum.