How did this tradition mutate? It was a long and complex process, in which the import of Wahhabi theology via the great madrasah at Deoband played an important part. But underlying and making that possible was resistance to colonialism in general, and the Durand Line in particular. The shift to a more militant version of Islam provided tribal leaders with their vocabulary and their ideological rallying point. 

The evolution of Pashtun Islam, each successive manifestation becoming more extreme, has been a highly structured process. The teachings of Pashtun scholar-priests are handed down orally through a formal "pir-murdi" (teacher-disciple) lineage, and with the 1897 jihad they decisively changed direction: away from a faith that emphasised the individual's contemplative relationship with God, and towards one emphasising strict observance and obedience. The continuities between Durand's era and ours are striking. For example, the 1890s saw the establishment of Societies for the Prevention of Vice and Promotion of Virtue, ruthless means of enforcing conformity. They reappeared under the same title when the Taliban emerged under Mullah Mohammed Omar in the 1990s. 

The most important leader of the 1897 revolt was a cleric known as the Hadda Mullah. He had a contemporary biographer, Mia Abdul Baqi, who produced a manuscript copy of his life. It has never been published. But by the late 1980s, the manuscript was in the possession of none other than Gulbuddin Hekmatyar — the most powerful of the many Pashtun commanders who fought against the Soviets with American aid, and went on during the following decade to become a close ally of Osama bin Laden and the Taliban. Still waging war against the Karzai government and its Western allies, Hekmatyar's forces dominate Kunar, where Linda Norgrove was kidnapped. 

Among the people of the frontier there is a rich oral tradition, which remembers the Hadda Mullah and his comrades as mujahiddin — the term for holy warriors also used to describe those who fought the Soviets in Afghanistan. "The jihads against the British were a special type of war, what we call a ghazar," Nizar Mohammed, 76, told me in Mardan, near Peshawar. "That means, a war in which the prophet has a personal stake. That's how our people saw it." Just as Irish Republicans memorialised the struggle against the British in their rebel songs, Pashtun children still sing verses that commemorate the battles of 1897 and after. One of the most haunting celebrates a warrior called Beram Khan, and imagines the words of his wife: "O Beram Khan,/If your body comes back with countless bullets in your chest,/I will never mind./But I don't want to hear that you left the battlefield fearing death./If you are martyred defending your country, /I will weave your shroud with the hair from my head."