And after the 2001 terrorist attacks on America and the U.S.-led wars in Afghanistan and Iraq, that idea took on an aura of inevitability.
But Tariq Ramadan says the notion of a "clash of civilizations" fails to take into account the fact that Muslims already comprise an integral part of Western civilization.
"I think we have to go beyond this binary vision of reality, you know, and the struggle is not on the borders. The struggle is within our [Muslim] society, because we are experiencing democracy. We are free. We can speak. Even though it is very difficult, even though we have still prejudices, discrimination. But the Muslims -- the European, the American, the Canadian -- should be involved in their society," Ramadan says.
Ramadan made his remarks yesterday at an interfaith conference in Prague that was sponsored by Vaclav Havel, the former Czech president.
Other conference participants challenged what they said has long been an unquestioned democratic principle on the separation of church and state.
Tomas Halik is a prominent Czech Roman Catholic priest, former dissident, and present professor at Prague's Charles University.
"That principle no doubt has historical justification -- it protected political and civic freedom from the dangerous domination of a powerful church or churches, as well as the freedom of the churches' independence from state interference. But I think that there are many reasons why we can no longer accept this principle as a paradigm for understanding the relationship between religion and public life," Halik says.
Halik offered instead an approach that he called "autonomy and cooperation" between governments and religious faith.
The panelists included other Catholics, rabbis, a prominent Shinto leader from Japan, and Protestant Christian thinkers.
Hanna-Barbara Gerl-Falkovitz holds the chair of philosophy of religion and comparative religious studies at the Technical University of Dresden in Germany. In the conference, she supported Halik's view that the idea of "separation of church and state" has served its historical purpose.
In the 20th century, she said, the world suffered through the rise of two powerful atheistic ideologies -- Nazism and fascism, and communism.
She said these ideologies imposed absolute separation of church and state. And they resulted, she said, in governmental dismissal of religion as little more than superstition.
Ramadan also supported limited and positive interaction between the spiritual and the civic. Without that interaction, he said, governments forfeit access to a valuable source of ethical and moral guidance. Ramadan warned, however, that the interaction should not rise to the point at which a government claims a special relationship with God.
"To have more morality in politics is necessary. But not to use or to instrumentalize religion in order to say 'God bless our country.' I think that God blesses -- and should bless -- all the countries and all the way...and what is just is just everywhere and is not just because it's our country. So this perception that God is with us and not with you, I think is wrong," Ramadan says.
Ramadan says that he has taken on as part of his life's work "to think about Western Muslims and the way we can remain Muslims and at the same time be Westerners."
He says that work often has made him and his ideas less than popular both in the West, where he was born and educated and chooses to live, and among his fellow Muslims.
"And I knew from the very beginning that my task was controversial. Because I want to be in the middle of two things, two worlds. I'm a European Muslim; I'm a Western Muslim. So it's obvious that when you speak like this you will have traditionalists and literalists saying that you are betraying the religion. So it is controversial within the religious community. But at the same time, I'm still too much Muslim for some Europeans and some Americans. Because, 'Oh be careful. This is still Islam. Islam is too much Islam already,'" Ramadan says.
Ramadan's balancing act between Western and Islamic society has at times turned bitter. In France and the United States, he has been accused of rhetorically supporting militant Islam among Muslims while saying the opposite to Westerners.
Ramadan strongly denies those allegations and points to a series of articles he has written condemning all forms of terrorism.
But following a media campaign by his American critics, the U.S. government last September refused to grant Ramadan a visa to teach Islamic ethics at Notre Dame University in the Midwest state of Indiana.