Imagine that every day, the media were reporting a new outbreak of jihad warfare across the Muslim world, from the Atlantic to the Pacific, across the Middle East and North Africa, and deep into Central Asia. Imagine moreover that this violence was not confined to isolated terrorist incidents, but involved vast well-organized armies, some tens of thousands strong, many with modern weapons. And in some instances, jihadi forces have overwhelmed European armies, slaughtering thousands of infidels.
Surely, this sounds like the ultimate fantasy of an al-Qaeda chieftain, and if such a thing ever did occur, it would be indelibly preserved in the history books. Few would deny claims of a worldwide clash of civilizations, and of faiths.
In fact, those events did happen precisely as described, and not back in the golden age of the Caliphate, but less than a hundred years ago. As recently as the 1920s, the Muslim world passed through an era of mass religiously-driven revolution, which would lay the foundation for most later political developments in that region. How could the world ever have forgotten such a thing?
During the 19th century, all the European colonial powers had built empires in Africa and Asia, usually at the expense of Muslim powers and populations. In terms of its Muslim population at the start of the 20th century, the British Empire was by far the world's largest Islamic realm, followed by the Dutch and French possessions. British India alone was home to almost a third of the world's Muslims.
Still, resistance never faded, and it gained new strength as European powers slaughtered each other during the First World War. Even better from the nationalist point of view, each Power tried to undermine its enemies by trying to stir up revolution in its colonial possessions. Ironically, European states were fuelling radical nationalism, usually in Islamist forms. Driving Muslim activists to still greater militancy, the end of the war marked the end of the old Ottoman Empire -- the last remaining Muslim Power -- and the Caliphate itself was officially wound up in 1924.
In the decade after 1918, every colonial Power confronted Muslim insurgencies on an unprecedented scale. Not only did anti-colonial risings rage across the Islamic world -- a global Arc of Crisis -- but many drew their inspiration explicitly from religious teachings. They were usually led by Islamic religious figures, by sheikhs or qadis (judges). Suddenly, an armed and transnational Pan-Islamism seemed like a realistic prospect. If we want to visualize inter-religious struggle in these years, we should imagine a European biplane dropping bombs or gas on a Muslim village, and the aircraft might bear the colors of any one of half a dozen nations.
Europe's empires could only restore order by deploying massive violence. In Libya, Mussolini's regime launched a heavy-handed campaign against the Senussi resistance, killing thousands of civilians and imprisoning many others in concentration camps. They executed the resistance leader Omar al-Mukhtar, a pious Senussi sheikh. Between 1919 and 1925, Britain's newly founded Royal Air Force saw action against Muslim rebels and enemy regimes in Somalia, Afghanistan, Waziristan and Iraq.
The Russians too faced their Islamist challenges. In fact, the seventy years of Soviet history possess a neat symmetry. As we know today, the regime was ultimately crippled by its Afghan war of the 1980s, but the Soviet Union was also born in a struggle against jihad, in Lenin's time. Following the collapse of Tsarist rule, Muslim peoples of the Russian-ruled Caucasus began an insurrection intended to create a state based on the strictest interpretation of Shari'a law. The movement reached its height in 1920 in the regions of Daghestan and Chechnya, both areas that have seen ferocious violence in modern times.
Muslim Turkestan was the scene of the widespread Basmachi revolt, the Basmachestvo, led by former Ottoman officers. The Basmachis ultimately fielded tens of thousands of guerrillas, fighting on behalf of an autonomous Sharia state, and operating across most of Soviet Central Asia. The Bolsheviks did not control the region fully until the mid-1920s, and some rebels fought into the next decade.
By far the greatest Islamic victory came in Morocco and northwest Africa, where the resistance was led by the sturdily independent Berber tribes, particularly those in the mountainous Rif region. Resistance focused on a tribal leader and qadi called Abd el-Krim. During a dazzlingly effective guerrilla war in 1921, his forces crushed Spanish military power in Morocco. They killed several thousand European soldiers, leaving him the head of a short-lived Rif Republic. In 1925, French and Spanish forces responded with an invasion on a First World War scale, with several hundred thousand troops supported by tanks, aircraft and mustard gas.
In the traditional core of the Muslim world too, fundamentalist forces rose -- against the new Kemalist regime in Turkey, and even against the emerging kingdom of Saudi Arabia.
Although these revolutions were eventually suppressed, the radical climate of this decade left long memories. It was in 1928 that Egyptian Islamists formed the Muslim Brotherhood, which since 2012 has dominated that nation. Another heir was India's Maulana Mawdudi, the theoretician of radical Islamism worldwide, and the inspiration for modern Pakistan's jihad movements. The same years produced other key activist movements, such as India's missionary order, the Tablighi Jama'at.
Meanwhile, the Iraq revolt resulted in the great Shi'ite school of Najaf moving to Qom, in Persia. Already in 1921, the nineteen-year old Ruhollah Khomeini was a student at Qom, long before his later elevation to the prestigious rank of ayatollah. Like his counterparts in Egypt, Palestine and British India, Khomeini grew up seeking a world order founded on a primitive vision of authentically Islamic religious authority.
European historians are familiar with the sweeping changes that the First World War caused in the West, with the upsurge of new ideologies, and the transformation of culture. But the same is also true for the Islamic world. That war made all things possible, and the world is still dealing with the consequences.