THE big surprise, viewed from my own narrow perspective five years later, has taken place in the mysterious zones of extremist ideology. In the months and weeks before the invasion of Iraq, I wrote quite a lot about ideology in the Middle East, and especially about the revolutionary political doctrine known as radical Islamism.

I tried to show that radical Islamism is a modern philosophy, not just a heap of medieval prejudices. In its sundry versions, it draws on local and religious roots, just as it claims to do. But it also draws on totalitarian inspirations from 20th-century Europe. I wanted my readers to understand that with its double roots, religious and modern, perversely intertwined, radical Islamism wields a lot more power, intellectually speaking, than naïve observers might suppose.

I declared myself happy in principle with the notion of overthrowing Saddam Hussein, just as I was happy to see the Taliban chased from power. But I wanted everyone to understand that military action, by itself, could never defeat an ideology like radical Islamism  could never contribute more than 10 percent (I invented this statistic, as an illustrative figure) to a larger solution. I hammered away on that point in the days before the war. And today I have to acknowledge that, for all my hammering, radical Islamism, in several of its resilient branches, the ultra-radical and the beyond-ultra-radical, has proved to be stronger even than I suggested.

A lot of people right now make the common-sense supposition that if extremist ideologies have lately entered a sort of grisly golden age, the Bush administration’s all-too-predictable blundering in Iraq must bear the blame. Yes, certainly; but that can’t be the only explanation.