"The real genesis of Al Qaeda violence has more to do with a Western tradition of individual and pessimistic revolt for an elusive ideal world than with the Koranic conception of martyrdom".
This seems to me to be a more useful approach to modern violence of this kind than recent attempts to identify the harmful ideology behind the attacks in London or Sharm el-Sheikh. In the UK, a lot of attention has recently been paid to the fiery clerics operating in Britain who are thought to have inspired the London bombers. This is relevant and useful, but at the end of the day, the violence is carried out not by those clerics, but by their hearers. Comparisons with 1970s anarchists, or even with their 19th century forebears in Russia, suggests that it is nihilism in search of the cause that is the constant in the most savage acts of this kind. Looking at Binladenism, it seems that nihilism is the essence and the pursuit of a caliphate is the accidence. Which leads to the conclusion that defeating the ideology of Binladenism will bring only temporary respite from acts like 9/11 and the London bombings.
(Incidentally, the New York Review of Books publishes some excellent articles on the Middle East, many of which are free on the website. This issue has an illuminating essay on the Ahmadinejad phenomenon in Iran by Christopher de Bellaigue, and a somewhat alarmist look at rising Iranian influence in Iraq by Peter Galbraith. Last month had an essay on the PA and Hamas by Robert Malley and Hussein Agha).