Most people will have called someone a “fascist” in moments of anger, usually a young person arguing with an older conservative. For the term has never been confined to the ideologies and movements of interwar Europe that bore the name.

In recent months the use of “fascism” has migrated from left to right while spreading to the Islamic world. Tariq Ramadan, the Oxford-based Islamist ideologue, speaks of the (western) “fascism which kills innocent people in Iraq”. President George W Bush has announced that “this nation is at war with Islamic fascists”.

There are many understandable reasons why Bush is resorting to this language. “Fascism” enables the administration to give a familiar face to a shapeless enemy; it makes Al-Qaeda comprehensible on our terms by slipping a metaphorical Nazi steel helmet over the keffiyehs and balaclavas of the terrorists.

The legitimacy of fighting “fascism” is something that almost everyone can sign up to. But it begs the question as to whether militant Islam is “fascist”. Could one not equally refer to “Islamobolshevism”, since some of the main Islamist ideologues were fascinated by the idea of a revolutionary vanguard, even as they rejected Marxist atheism?

It is not hard to find direct links beyond the enthusiastic credulity of their respective adherents towards charismatic charlatans. There are also direct influences. One of Hitler’s greatest admirers was Grand Mufti Haj Muhammed Amin al-Husseini, an uncle of Yasser Arafat, who spent the war in Berlin urging the Führer to exterminate Jewish people. Ahmad Fardid, the Iranian philosopher, introduced the mystifying existentialist philosophy of Martin Heidegger to the young President Mahmoud Ahmadinejad.

I think we can do better by examining states of mind. Nothing much separates the horror that modern Islamists express towards western urban industrial society and the cultural pessimism that was pervasive on the European right in the late 19th century — the toxic pool from which fascism emerged in the aftermath of the great war.

Most European fascist movements were products of visceral national grievance; a colossal sense of collective victimhood at the hands of the Israeli David or the western Goliath is also a key motivating force behind radical Islam.

Interwar fascists believed in the purifying efficacy of political violence, glorified death and destruction and were contemptuous of liberal democracy and the rule of law. Radical Islamists may detest democracy for different reasons — as a form of blasphemy against Allah’s will rather than what elite fascists regarded as the politics of the mindless herd — but they share a similar nihilistic pleasure in chaos and destruction.

Like fascists and communists, they are psychologically captive to one big idea and are equally willing to kill, or to die, for it. Their big idea is that Muslims should be on top rather than so manifestly powerless vis-à-vis the western world.

Fascists believed in a politics of fall from a heavily mythologised paradisiacal past, casting themselves as the light that will dispel the darkness. “Germany awakes” is paralleled by the “blessed awakening” of all Muslims that tantalises Osama Bin Laden.

Like radical Islamists, fascists were fascinated by modern technology, albeit tank and tractor factories rather than satellite phones, but the visions of greatness that animated them lay in the remote past: ancient Rome in the case of Mussolini, or the medieval Reich which Hitler promised to restore a third time, although he was also fascinated by prehistoric Aryans. Al-Qaeda is similarly driven by a desire to recreate a caliphate that existed 1,300 years ago.

Before we, and Bush, get too carried away with “Islamofascism”, clearly there are huge contextual differences. Militant Islamists are utterly murderous and viciously anti-semitic, but the heterogeneous ethnic composition of Al-Qaeda hardly suggests that visions of racial purity matter to it. In fact, Al-Qaeda is doing its best to recruit white and black people in order to outwit authorities looking for Arabs and Pakistanis.

Fascism emerged as a form of “anti-politics” designed to bridge endemic conflicts between capital and labour. It favoured corporatist economics, in which employers and workers would be dragooned by the state. These doctrines have little bearing in economies of entrepreneurs and traders. Before his mafia-like Sudanese hosts stole his money in the late 1990s, Bin Laden was a (not very proficient) venture capitalist, ploughing his (modest) fortune into forlorn business endeavours to bankroll terrorism.