The streets of France rang with cries for unity this weekend, as more than 4 million people marched in a defiant response to three days of terror that left 17 people dead. French officials said Sunday's march in Paris was the largest in the nation's recent history. "National unity is vital at such a time, because the plans of the terrorists go beyond violence and seek to sow fear," French Interior Minister Bernard Cazeneuve said last week, amid the deadly attack on the satirical newspaper Charlie Hebdo and subsequent twin hostage crisis. Yet for all the emphasis on unity, the attacks have also brought renewed attention to the widening social and political divides in France. As the violence was perpetrated by three French men with immigrant parents and a violent interpretation of Islam, far-right parties across Europe have argued that they've been proven right about the threats posed by Islamic extremism and immigration. "I have been warning of the danger of Muslim fundamentalism in our country for years," said Marine Le Pen, leader of France's National Front party, in the wake of the attacks. Le Pen's deputy, Florian Philippot, told French radio: "Anyone who says Islamist radicalism has nothing to do with immigration is living on another planet." Meanwhile, the political opponents of far-right parties across Europe have accused those parties of exploiting the attack to sow fear between communities. Though French society does, indeed, have deepening schisms, many analysts say this has little to do with the dire warnings of the far right. The hard-liners' focus on religious differences can obscure the country's underlying socio-economic divisions, Anand Menon, a professor of West European Politics at King's College London, told The WorldPost. France's economic decline after the 2008 financial crisis has reinforced the gulf between the employed, who have relatively generous social benefits, and the growing numbers of unemployed, especially among youth and minorities. "There is a growing division between the economic insiders and outsiders," Menon told The WorldPost. "The outsiders include a disproportionate number of North Africans living in the horrendous suburbs of Paris -- which are almost like another country." The banlieues, or suburbs, of Paris are home to many impoverished immigrant communities, and have high levels of unemployment and crime. The banlieues erupted into major riots in the 1980s and again in 2005. "We have a terrible problem in France of disenfranchised young people, with no opportunities," Olivier Roy, an expert in political Islam, told The New York Times last week. "Many of them start off in petty delinquency, but for some of them radical Islam is a way to find a second life." Meanwhile, the National Front has tapped into discontent over those same economic disparities, but blames immigration for making the problem worse (an argument of which many economists are skeptical). A significant economic divide exists between rural and urban France, and last year, Le Pen made a point of touring impoverished rural areas, which she labelled "forgotten France," according to the BBC. The party's popularity has surged. In France, as in other European countries, politicians and the media frequently treat Muslims and immigrants as one and the same. Yet most immigrants to France are not from Muslim-majority countries. Nearly half of new immigrants to France in 2012 were Europeans, according to the French national statistics agency INSEE. The agency notes that the number of new immigrants to France was stable between 2004 to 2009 and rose between 2009 and 2012, mainly due to an influx of Europeans after the financial crisis. While France does not keep official statistics on religious affiliation, statistics indicate that a growing number of French Muslims are also French citizens. The French Muslim population is estimated to be the largest in Western Europe -- approximately 7.5 percent of the population, compared to an estimated 5 percent in Germany and the United Kingdom. French Muslims are predominantly North African, the descendants of migrants from former French colonial territories. By contrast, Britain's Muslim population is historically from South Asia, reflecting the country's own colonial past, and Germany has a greater proportion of guest workers from Turkey. Such nuances get lost, though, when political leaders do things like comparing Muslim immigration to the Nazi occupation of France, or saying that the onus is on Muslims to prove that "you can be French and Muslim and still respect secular rules." Muslim communities across Europe are grappling with a number of serious problems, including radicalization by extremist groups and populist backlash against Islam. France is reported to have the greatest number of Muslims going to fight alongside extremist groups in Syria, although the percentage of French Muslims who have gone off for that reason is about the same as the percentages in the U.K. and the Netherlands, according to one estimate by CNN. At the same time, far-right groups are growing in visibility and popularity across Europe, and attacks against French Muslims are on the rise. The uptick in racist violence has not only targeted Muslims. France also has Europe's largest Jewish population, and many French Jews fear that a surge of anti-Semitic attacks is in the offing. Violence against Roma communities has also escalated in recent years. Nicholas Dungan, a senior fellow and France expert at the Atlantic Council, argues that the root cause of rising racism is a general malaise about the country's prospects. "If you look don't think things will get better, you look to blame someone else," he told The WorldPost. "France has been in a state of drift for some time now, and that drift has led to divisions." Perhaps surprisingly, the people of France have a relatively high opinion of the Muslims in their country, according to a Pew survey in March 2014. Pew found that 72 percent of the French regard French Muslims favorably -- a higher percentage than found in Italy, Greece, Spain, Poland, Germany or the U.K. At the same time, a similar percentage of French respondents -- 74 percent -- believe that Islam is incompatible with French values, according to an IPSOS survey in 2013. Dungan argues that there is no contradiction between these statistics. "French people are politically sophisticated enough to make a distinction between Muslims and fundamentalists," he said. "There is a lot of consistency in saying, 'We believe that Muslims are perfectly capable of being good members of society, but we don't think the values of Islam' -- and they're likely thinking of extreme examples -- 'fit with our values,'" he said. This is reflective of wider political debates in France about the role of religion. Historically, France has drawn a strict separation between private religious practice and the secular public sphere. This has caused tensions with religious communities -- for example, many Muslims are displeased about recent bans on in schools and face veils in public. French national identity is particularly rooted in the founding values of the Republic: liberty, equality and fraternity. Dungan argues that France is beset by an identity crisis after struggling to articulate these values in the modern era, noting a failure of political leadership, economic problems and a sense that France has faded on the world stage. "If France does not excel, France does not exist," he remarked, characterizing French national pride. Many commentators have warned of the risk of further polarization following last week's killings. "The main impact may be to use the attacks as an excuse to blame Islam and immigration for broad anxieties about where things are going in Europe today," warned John R. Bowen, sociocultural anthropologist at Washington University St. Louis, in a school publication. Others, though, are more optimistic. Several Parisians told the Financial Times that they hope the attack will provide an opportunity to heal the country's divisions. And Dungan believes that is already happening. Values are again at the center of national debate and the crowds on the streets show how deeply they are shared. "Until now, the National Front was able to occupy an empty political space," he said. "But now people have realized that you don't need to vote for the far right in order to be patriotic."