Instead, in Faisal Shahzad — a 30-year-old graduate of computer science with an MBA from the University of Bridgeport, Conn., and married with two young children — we have the profile of an alleged Islamist terrorist coming from a middle class, or even privileged, background.

The cause of Islamist terror is Islamism. It is an ideology like bolshevism devised to legitimize making war (jihad), seize power and establish a Shariah-based totalitarian rule. And as it was once with bolshevism in old Russia, Islamism attracts primarily young Muslim men of middle-class backgrounds with intellectual pretensions to become the vanguard “martyrs” of jihad against the West for being the enemy of Islam and Muslims.

Islamism flourishes in an environment of acute resentment born from a sense of general failure of society compared to past greatness or glory nostalgically idealized. The greater the sense of present failure of Muslim societies, the more pressing the Islamist fervour to redeem an idealized past, and in this effort all means become justifiable for an end that is given religious sanction.

Islamism is the Muslim ideology of counter-revolution against the modern world and modernity. And while this ideology keeps the elders engaged through long idle hours of endless chatter, it is the opium readily inhaled by the young that sets so many of them on the path of jihad against infidels.

Pakistan is the fertile breeding ground of Islamism for reasons that are intrinsic to its history and politics. It is the only country forcefully established with Islam as a nationalist ideology that a majority of Muslims in undivided India — including Muslims of what constitutes present-day Pakistan — rejected.

Since Britain conceded to the demand for Pakistan in the face of religious frenzy pushed by middle- and lower-class Muslim activists, the country’s history has been a series of failures of its own making. These failures have deeply embittered the thinking of that class of Pakistanis from whose rank the ruling elite comes, and whose regular pastime is to parcel blame to others for their part in making Pakistan a terrorist-exporting rogue and failed state.

I have traveled in Pakistan . I have visited the homes of the privileged in society and there among the wealthy and the powerful, I have often heard the case made that if Pakistan is faced with destruction it will destroy the other as it goes down. In Urdu this sounds terribly ominous.

Young Pakistani men like Faisal Shahzad, whose father is a retired air force general, hear such discussions and are invariably influenced by them.

The list of Pakistani terrorists is long and getting longer. It has long been urgent for the West to respond effectively to Islamist terrorism.

One response might well be to consider a moratorium on migration to the West from Pakistan and adjoining areas producing hordes of men such as Faisal Shahzad.