I imagine a lot of American Muslims this week feel like the Irish once did in London after an IRA bombing there: let this massacre not be by one of ours, dear God. But it was.

Fort Hood was the work of Nidal Malik Hassan, an American Muslim. Not an immigrant, not a September 11 kamikaze intruder, but the home-grown product: the all-American boy who turned on his own people and his own army for politico-religious reasons.

Obviously, most American Muslims want to live in peace with their fellow Americans. But within, it seems, all ‘moderate’ Muslim communities, are some fundamentalists who hold the local |franchise for the global grievance of Islam.

And no one really knows what such Islamic fundamentalists want, because the demands change according to whatever market the local Islamic franchisee is operating in. But at the bottom, jihad — the holy struggle — is the key liberator which enables the Muslim fundamentalist to depart from the rules of the society in which he is living.

Jihad can be formed as a result of the teachings of an imam, but it boils down to a personal contract between Allah and the believer, based on an extreme interpretation of Islam. This effectively declares: “If you feel very strongly that the rules in the Holy Koran about never injuring the innocent, and always respecting women |and children, and respecting the rights of the kaffirs to remain non-believers, are subordinate to jihad, then these rules do not apply to you.

“Moreover, if you feel specifically enjoined to break these rules in pursuit of jihad and martyrdom, the reward shall be paradise and all the blissful wherewithal of the heavenly hereafter.”

This notion of a personal contract with Allah, that authorises a believer to break even the most civilised and civilising laws of the Koran, is a sure-fire recipe for murderous irrationality and social anarchy.

And these have become the defining feature of almost every Muslim society in the world. So where there are no Muslims, the problem of jihadist terrorism does not exist either. It is the most obvious statement imaginable, yet it is worth making. Bolivia, Paraguay, Chile, Iceland, Japan, Mozambique, Taiwan — they do not have Muslim immigrants, and so do not have the problem of Islamic terrorism.

Here, then, is the San Andreas fault within Islam, on which tectonic disjuncture just about all 20th and 21st century Islamic societies have fallen apart.

No matter how much the majority Muslim population seeks to live in peace and friendship with their neighbours, if enough fundamentalist mavericks feel they have received their heavenly mandate, then the result is the same, and even within outwardly benign communities.

Hence Fort Hood Texas, September 11 New York, July 7 London, Holland, Denmark, Belgium, France, Norway, Bali, Kenya, Tanzania, Iraq, Somalia, Yemen, Iran, Anatolia, Egypt, Algeria, Jordan, Iran, Iraq, Afghanistan, Pakistan, Bali, Bombay and Australia. Such universal belligerence has no universal cause, other than in the universality of Islam, which seems so often to respond lethally to local conditions, whatever they are.

To be sure, there is no such thing as a single, typical, Islamic society. The barren and barbaric Hindu Kush is not the same as the perfumed court of the Ottomans. But somewhere inside the greater Islamic mind is an absurd sense of victimhood: and where there is no local grievance, why then there is always ‘Palestine’, as if those few disputed acres in the vast Islamic landmass of Afro-Asia merited the unanimous and indignant global furies of all Muslims, from Delhi to Dearborn.

This same querulous organ of self-pity also resents Muslims becoming the subject of intelligence operations after an Islamic atrocity, as if it were reasonable and wise to subject Mexican laptop-dancers and Lapland reindeer-herders to equal levels of scrutiny and suspicion. India has been the home of Islamic moral-secessionists for longer than anywhere else. And the Indian intelligence services are often almost paralysed in their hunt for Islamic terrorists by the political power of Muslim ‘community leaders’ who unfailingly denounce terrorism — but then equally denounce any action by Indian intelligence against members of the Muslim communities.

Such actions, it is argued, are clear proof of the fundamentally Islamophobic nature of the Indian state and the reason for the fundamentalists' actions in the first place.

This is a sealed moral system, an internal autonomy that is immune to penetration or logic. Fear of such accusations of Islamophobia — phobophobia — almost certainly prevented Major Nidal Malik Hasan's superior officers from disciplining him for his public jihadist outpourings.

Pre-emptive action would certainly have been portrayed by the liberal media as Islamophobic |discrimination against a patriotic Muslim, and would have enraged that reliable stock-character of media portrayal, ‘moderate Muslims’.

Thirteen genuine patriots are now dead as the price of such phobophobic appeasement.

More importantly, the US must now wake up to the consequences of its open-door immigration policy, just as Britain did four years ago after July 7.

The subsequent pattern will presumably be similar.

Watch now, as ‘victimised’ American Muslims close ranks, the burka and the hijab become commonplace amongst their womenfolk and the rest of the US asks in tones of awestruck horror: My God, what have we done?