Groups employing successful terror tactics usually had the winds of historic change behind them, most obviously in the case of nationalist movements in their fight against colonial rulers. The most successful terrorist organisations are like judo black belts who know how to leverage an opponent's strength against them. The US was forced into a series of armed responses by 9/11 with unforeseen wider ramifications. Since 9/11, the West and its allies have learned some lessons, the main one being that we are not going to kill or capture every Islamist terrorist. Force is increasingly accompanied by amnesties and buy-outs of low-level jihadis. This has been recommended by US commanders and our own David Miliband, who now tellingly refers to the Taliban as "conservative nationalists". This approach assumes that such men are solely motivated by local or mercenary considerations. This is not true of Yemeni jihadis — whose hatred of the West and Israel is immense — and it may not be true of those Taliban to whom we are about to direct a lot of Japanese yen. 

Interrupting the spiral of radicalisation is also important. There are a number of "decompression" programmes for young extremists and jihadi drop-outs in Egypt, Indonesia, Saudi Arabia and Singapore, schemes which aim to reintegrate young men into family life and normal careers. These schemes may work in rich countries but are unlikely to be efficacious wherever youth unemployment is rampant. 

Raising the jihadi drop-out rate is Jacobson's main concern in a report published last August by the Washington Institute for Near East Policy. Since a person of Muslim origin is 54 times more likely to be killed in an al-Qaeda attack than a non-Muslim, we should be emphasising each instance of terrorist "mis-targeting", such as the incidents in which a 12-year-old Egyptian girl was killed or an entire Jordanian wedding party wiped out, provoking an angry backlash. The dependence of terrorist groups on crime for funding is another form of hypocrisy worth highlighting. The West also needs to puncture romantic myths about the jihadi lifestyle. Even within al-Qaeda there are constant squabbles between its Egyptian "pharaoh" strategists and the Yemeni "dervishes" killed executing their plans. Jacobson thinks we should be publicising exit routes, as the Italians successfully did with the Red Brigade, if only to gain the actionable intelligence which is often lacking. 

None of these tactics will win the struggle, but it is good that people are studying history to show that there can be a positive outcome.