LISBON, Portugal — Muslims are everywhere in Europe.
They are driving cabs in Amsterdam, reading the news on French TV, cooking pasta in Roman restaurants. They are surgeons operating in Brussels' hospitals, businessmen making millions in London, shopkeepers selling beer to late-night revelers in Lisbon.
Across the European Union there are around 20 million Muslims, citizens and immigrants alike, doing pretty much the same as their non-Muslim neighbors.
So why do so many still think of Islam as something foreign to Europe?
Recent terror attacks carried out by gunmen espousing radical Islam have put many Muslims in the position of defending both their faith and their status as members of European communities.
In the wake of the Jan. 7-9 terror attacks in Paris, in which apparent extremists killed 17 people — most in shootings at a kosher supermarket and the office of a satirical newspaper that had published caricatures of the Prophet Muhammad — community leaders have been struggling to emphasize the normality of Muslim life in Europe.
"Our challenge is to clarify things, to show people that Islam is not what they fear it is," explains Sheik David Munir, imam of Lisbon's Central Mosque.
"We are a normal part of society," Munir told GlobalPost. "Muslims here are Portuguese. They are living in their country. They speak Portuguese, their culture is Portuguese. The only difference is that they have their religion."
High-profile Muslims across Europe have been swift to roundly condemn the Paris attacks and the radicals who have managed to recruit up to an estimated 4,000 Europeans to fight with the self-proclaimed Islamic State (IS) and other extremist groups in Syria and Iraq.
Ahmed Aboutaleb, mayor of the Dutch seaport Rotterdam, went on TV to say extremists who are unhappy with the freedom offered in Europe should "f**k off."
The Mufti of Serbia, Muhamed Jusufspahic, last week described IS as "a Satan shrouded in something foul-smelling" that had gathered together the "biggest scum" of Europe to besmirch his religion.
Yet while prominent Muslims condemned the attackers, many were angry at the satirical newspaper Charlie Hebdo, too, which had mocked their religion in the name of free speech.
Community leaders complain such actions show a lack of respect for already marginalized groups, particularly discontented Muslim youths who are vulnerable to extremist propaganda portraying the West as a repressive enemy of Islam.
"Living in the 21st century, people have to learn to live alongside each other in respect," Munir says. "There's a marginalization in some parts of Europe that goes back many years, and it's going to take years to put things right. We need to be prepared for that. It's very important that we all play a role."
Europe's Muslims are a diverse bunch whose roots stretch around the world.
Muslims have lived in the Balkans and other parts of Eastern Europe for centuries. Islam is the majority religion in Bosnia, Albania and Kosovo. Muslim Turks make up around 13 percent of Bulgaria's population. There are small Tartar communities in Poland and Lithuania whose history dates back to the 14th century.
Western European nations invited millions of Muslims to counter labor shortages during the economic boom in the decades after World War II.
Belgium hired Moroccans to work in its steel plants. Pakistanis headed to the textile mills of northern England. Turks came to Germany to assemble Volkswagens and Audis. Algerians provided manpower for what the French call their "glorious 30 years" of economic expansion after 1945.
In recent years, more Muslims have come to Western Europe seeking refuge from conflicts in Bosnia, Somalia, Afghanistan, West Africa and the Middle East.
The small community of around 50,000 Muslims in mainly Catholic Portugal mostly has its roots in the African nations of Mozambique and Guinea Bissau.
Around the continent, many are successful and well-integrated. Europe's Muslim middle class is a significant demographic. But when economies run out of steam, as they have in Europe in recent years, migrants often find themselves the first to suffer.
French Prime Minister Manuel Valls has warned urgent action is needed to tackle a form of "apartheid" that victimizes Muslims and other minorities living in run-down inner-city neighborhoods or the grim high-rise suburbs that surround much of Paris and other French cities.
Problems of marginalization run across Europe.
British government figures show the unemployment rate among Muslims at twice the national average. Studies in Germany indicate decendents of Turkish Muslims are much less likely to reach university. French estimates suggest Muslims make up half of prison inmates, although they are less than 10 percent of the overall population.
"A territorial, social and ethnic apartheid has imposed itself on our country,” Valls told reporters in Paris last week. "Social misery is coupled with the everyday discrimination ... we have to face the reality of our country today."
The French government has won praise for its measured response to the Paris attacks, rejecting any stigmatization of the Muslim community and stressing the inclusive nature of French society.
President Francois Hollande warned that the aim of the extremists is to sow discord, and countered that "unity is our best weapon" against extremism.
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Hollande and Valls have seen their popularity soar since the attacks as French citizens of all backgrounds came together for massive street demonstrations against terrorism.
The number of Islamophobic incidents has risen sharply in France since the attacks, however — mainly small-scale damage to mosques or verbal threats and insults. But there has been no spike in support for the far-right National Front party, as many had feared.
Muslim police officer Ahmed Merabet, who was shot dead as he lay wounded on a Paris sidewalk after trying to stop two of the gunmen who attacked Charlie Hebdo, has been hailed as a national hero, along with Lassana Bathily, a young Muslim migrant from Mali who risked his life hiding customers during the supermarket siege.
Some commentators have been heartened by the response to the Paris killings in contrast with the suspicion and hostility that flared 15 years ago after the 9/11 attacks in the United States.
"In the medium term and longer term I'm more hopeful that this kind of terrible tragedy may make people on both sides more aware of their obligations towards each other," says Shada Islam, an expert at the Friends of Europe think tank in Brussels.
"Whether it was in Paris or other European capitals many, many Muslim community leaders, Muslims just generally were out there demonstrating," she said in a telephone interview. "Both communities are waking up to the dangers of this leading into a total confrontation."
Sustaining unity will be a test for many European countries where support for ultra-nationalist, xenophobic parties has grown in recent years. Far-right leaders have touted a told-you-so stance since the Paris attacks.
"Islam is dangerous, it's not like other religions and it should not be treated like other religions," Matteo Salvini, leader of Italy's Northern League party, told reporters in Milan. "In the name of Islam there are millions of people around the world, and even in the hallways of our own houses, who are ready to cut throats and kill."
European police and intelligence services share the concerns of community leaders that such sentiments could trigger a vicious circle by adding to the alienation of young Muslims, particularly those from deprived areas with little education and few job prospects — like the three susepected Paris terrorists.
"Mainstream politicians can counter the [far-right] narrative by pointing out that our societies are diverse, that talent is desperately needed, that Muslims have a place in society, that they are not foreign beings," says Islam, of Friends of Europe. "If you're excluding them from the start, if you are creating a very us-and-them approach, they won't feel any sense of obligation or ownership of Europe."
The French government has announced a series of measures to counter alienation. Like others in Europe, it is also seeking to enlist the help of Muslim communities to monitor for signs that youngsters are being tempted by recruiters from radical groups operating online, or on the ground in European cities.
"Community leaders have to do what they are starting to do much more vociferously, coming out and denouncing these attacks, monitoring their young people to make sure they are not being lured away by these extremist voices, keeping a watchful eye on the internet sites that their kids are going on to," Islam said.
It's a task that goes beyond the Muslim community. Among the handful of Portuguese recruits who have reportedly gone to fight for IS in Syria and Iraq are youths raised as Catholics who have headed off to the Middle East after a lightning conversion to Islam.
According to local media reports, most were converted and radicalized while living in poor immigrant neighborhoods in London or Paris. Some have been killed in Western airstrikes, and at least one is thought to have taken part in videotaped beheadings of IS prisoners.
Countering such threats, says Lisbon Imam Munir, will need a long-term commitment from the whole of European society. "That's a task for all of us. This is not just a responsibility of politicians, or the clergy or parents, or schools. It's very important that all of us are involved."