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An Egyptian Muslim Brotherhood supporter holds a banner reading in Arabic "Martyrs for Islam," as another displays a copy of the holy Koran during a demonstration in Cairo, Sept. 22, 2006.

When British authorities thwarted an alleged plot to blow up transatlantic airliners in August, President Bush called it "a stark reminder that this nation is at war with Islamic fascists."

To understand how fascism and Islam began being uttered in the same breath, it's useful to visit Atlantic Avenue in Brooklyn. A few weeks after Sept. 11, 2001, historian Paul Berman began trolling the Islamic bookshops on this street, where he had a major revelation.

"The scoop was to discover that the philosophy underlying al-Qaida was a deep and intelligent philosophy, a thoughtful philosophy," Berman says. "It was insane. It was murderous. It was pathological."

But it was a philosophy nonetheless.

Berman ended up writing a book about it, Terror and Liberalism, which many in government cite as influential on their thinking about the current geopolitical situation. A large portion of the book is about the Islamist writer Sayyid Qutb.

Qutb was executed by the secular Egyptian regime in 1966. But before that, he wrote a large portion of his work from a Cairo prison. In those writings, Paul Berman recognized the intellectual underpinnings of al-Qaida -- ideas strikingly similar to the European currents of the 1920s and '30s.

Al-Qaida and Fascism

Berman saw in Qutb's writing "the kinds of doctrines that one might find in reading the Nazi or fascist philosophers of the European past -- and the kinds of doctrines or writing that I could easily imagine might prove to be seductive."

Historians don't all agree on the definition of fascism, though they do seem to agree on certain aspects of it: Fascists believed democracies didn't work. And as World War II historian Michael Burleigh points out, "fascists are completely contemptuous of liberal democracy and the rule of law, both domestically and in the international sphere." Fascists also tended to believe in cosmic conspiracies, usually involving Jews, Communists or Americans.

Columbia University professor Robert Paxton, author of Anatomy of Fascism, says that historically, fascism was a form of "consensual dictatorship."

"A dictatorship with enthusiastic popular support, in democracies where people had grown to feel that the democratic way wasn't strong enough to get the country out of a crisis," Paxton says.

Modern Use of 'Fascist'

Many of those who use the term "fascist" to refer to Islamist radicals believe it is appropriate because Islamist radicals are aiming to impose their beliefs on other people. They seek to create a new Caliphate, or political community of Islam, and in this community beliefs would come from the top down.

"It is fairly clear that the people we are describing are all fascist," says former conservative Republican House Speaker Newt Gingrich, who is also a historian by training. "They are all prepared to use the power of the state to impose a totalitarian system on others."

But the problem with using a term like "Islamofascism," says historian Michael Burleigh, "is that it suggests to many people that Islam itself is fascist."

And that's why Douglas Streusand doesn't think the term works. Streusand teaches Islamic history at the Marine Corps Staff College in Virginia. He believes most Muslims interpret "Islamofascism" as a slur, one that leaves many in the Muslim world feeling alienated.

Professor Khaled Abou El Fadl, who teaches Islamic law at UCLA, agrees.

"The thing I don't think most Americans realize," says Abou El Fadl, "is all this Islam-hating materials, they reach the Muslim world."

"They [people in the Muslim world] are well aware that practically every single week, a new Islam-hating book comes out, a book that talks about Islam as an inherently evil religion, an inherently dangerous religion," says Abou El Fadl.

For former Pentagon advisor Richard Perle, the term "fascist" or "fascism" is an emotive term, which is applied with precision by very few people. Perle doesn't use the term "Islamic fascism." But he does believe that the fight faced by Western countries today is very similar to the fights they faced in the past -- the struggles between a liberal democratic vision and a totalitarian one.

And according to author Paul Berman, it's instructive to view Islamist terror groups through the prism of fascism because it reinforces that these groups can be defeated ideologically.

"If we can see that this movement has at least some of the qualities… that are similar to the fascism of Europe, then we can conclude from that, that it's possible to conduct an argument," Berman says. "And we should be conducting that argument."

To win the argument in the Muslim world, though, might require a whole new set of language -- language that does not inspire bitterness.