Debate is rife about the reasons for the rise of extremism among young immigrants in Europe. Several studies delved into the social dynamics inducing terrorism, and the psychological root causes that drive youth living the European culture to indulge in terrorist activities against their societies, in an attempt at a deeper understanding of the phenomenon to curb its spread in the future.
Questions have arisen about whether European governments have exerted enough efforts to help immigrants, especially Muslim immigrants, integrate into European society. Countless experts pointed to previous failures to integrate Muslims comprehensively in the European civil, political, and economic life, making some European Muslims more prone to fall for extremist ideologies. European governments are trying at present to respond to such fears through two-pronged strategies. The first focuses on further integrating Muslims into European society, and the second targets boosting security measures and tightening immigration and asylum-seeking policies to prevent extremism and combat terrorism. 
First: Factors inducing extremism in Europe
Over the last century, many European countries, especially in Western Europe, witnessed an increase in the number of Muslim immigrants. Studies show that the Muslim population in Europe is relatively small. However, it is widely increasing due to immigration and the high birth rate among Muslims compared to non-Muslims in Europe. These growing numbers of Muslims represent a concern for European governments’ economic and political policies. They fear that some of these Muslims may be inclined towards extremist ideologies and recruited by terrorist groups. These concerns hiked after the 11 September 2001 attacks. 
Terrorism and religious extremism in Europe
Terrorism in Europe is not historically tied to Muslims. The two attacks that took place in Norway in July 2011 were perpetrated by a right-wing, extremist Christian Norwegian. Other attacks have proven that terrorists may belong to any race, religion, or political ideology. However, recent attacks, such as the Madrid bombings by a terrorist cell inspired by Al-Qaeda in March 2004, the murder of Dutch filmmaker Theo van Gogh in November 2004 by a Dutch extremist Muslim, and the London bombings in July 2005, brought the local “Islamist extremism” to the forefront of political debate in Europe.
Islam has been the main focus of Europe’s migration and diversity debates. Many of these debates focused on how Muslims are separated from their host communities. Some have growing fears regarding the compatibility of Muslim values with the West’s liberal democratic values. Others fear radical religious beliefs might lead to local and violent extremism. They see that Islam’s fundamentalist interpretations man comprise certain ideologies that are far from modernity. These ideologies encourage immigrants to separate from their societies and practice violent acts against them as they do not conform with their religious principles. In some cases, some refugees turned to be the enemies of the West, its culture, and existence.
The West, meanwhile, together with its different culture, lifestyle, and practices that are not in line with religious teachings (from their viewpoint) has become an enemy in the Middle East. This can be called “ideological fear” because it comprises, one way or the other, other forms of ideologies, be they Islamism, fascism, anti-Semitism and all other ideologies that use violence as a tool for political change. 
Muslim immigrants in the West
Right-wing extremists use Islamist extremism to argue that Muslim immigrants are dangerous to the West’s security. At the same time, Islamist extremists use right-wing violent extremism to claim that the West is hostile toward Islam. They argue that there is a war against Islam, and this is evident in the calls for banning headscarves in France, Belgium and Germany, and banning minarets in Switzerland in 2009. They believe that these actions are clear indications of repression, injustice and hostility against Islam. 
In some cases, radical groups incite Western authorities to take tougher measures against Muslims. These measures separate young Muslims from their societies and make them more receptive of extremist messages and recruitment attempts. These messages are made more credible by community conflicts and restrictive political responses.
The feeling that Muslims face many grievances or that the West seeks to change or destroy or is at war with Islam paves the way for extremists to legitimize violence as a tool for self-defence. In their view, the “true” Muslim must fight against aggression; and violence is mandatory to defend one’s faith and threatened Muslim “brothers and sisters” around the world. This way, extremists convince Muslim immigrants that they must adopt violence against Western grievances. 
On the other hand, the Muslim minority in Europe faces various forms of underestimation and exclusion. There are many studies that document public anti-Muslim sentiment, not just right-wing populist movements and politicians. This enmity is evident in the statements of politicians who argue that Islam is incompatible with Western values and beliefs. For example, the German interior minister publicly stated that “Islam does not belong to Germany.” In Europe, Islamophobia against Muslim immigrants appears to be more widespread than xenophobia. 
Second: The “Muslim immigrant” phobia and polarized groups in Europe
In 2007, the Danish Security and Intelligence Service (PET) pointed out that the biggest threat to countries like Denmark, and most European countries, comes from small, undeveloped groups of young Muslims, who sympathize with Al-Qaeda’s global jihad ideology. These groups can operate independently without control, support, or planning. They can also choose objectives, plans, and finance, and carry out terrorist acts on their own. This is called “Homegrown extremism.”  Homegrown terrorism is defined as violence mostly directed against targets in Western countries, where terrorists were born or raised, to achieve political, ideological, or religious goals.
In Europe, the stereotypical image of the immigrant, especially the Muslim immigrant, played a central role in increasing the phobia of many European Union citizens. This led to the emergence of the concept “migrant phobia”, and the spread of racial discrimination in these countries.
The stereotype of a Muslim immigrant in Europe
- The dominant stereotype is that the immigrant believes in a religion other than Christianity, and therefore represents a religious danger that should be feared and must be addressed.  This image of Christian public minds resonates with the feverish propaganda that papal leaders led during the Crusade.
- The immigrant has a culture and a pattern of customs and traditions that cannot be compatible with the Western culture.
- The immigrant represents a demographic risk due to two reasons. The first is the rising birth rate among Muslims, and the second is the “disturbing” decline of newborns among the European population. There are also current expectations that some European cities may have a Muslim majority between 2020 and 2025.
- The immigrant is a source of violence, terrorism and extremism. This image was reinforced by terrorist acts against public figures in the West and the racist perceptions of Muslim immigrants as blood-shedding terrorists.
Perceiving refugees as a security risk has serious consequences, such as the polarizing effect on democratic societies, and the exploitation of the right-wing media of any possible link between immigrants and violence.
Leftists, on the other side, often reduce the potential threats of immigrants. In the United States, Donald Trump, in his election campaign, focused on what can be described as worry concerning strangers. In late 2017, the US president eventually passed a travel ban on foreign nationals from several countries (mostly Muslims).
Xenophobia also existed in the Leave campaign accompanying the UK’s referendum on the Brexit in 2016. In Europe, the influx of more than one million refugees in 2016 alone reinvigorated far-right movements. This influx also led to increasing the popularity of national political parties, such as the National Front of France and the Alternative for Germany (AfD). For example, the AfD won the parliamentary elections on 24 September 2017, coming third with 90 seats to be the first extremist national party to win seats in parliament since World War II, which led to anti-fascist protests in Berlin.  In December 2017, thousands of right-wing supporters marched in Warsaw, Poland, with anti-immigration slogans and signs of abuse directed against Muslims in Europe. This emerging polarization is a great threat to Europe’s stability.
Surveys conducted in Europe showed that the stricter the religious beliefs and behaviour of Muslim immigrants, the less welcoming the European communities are. They also show that rejection and exclusion exist where there are large Muslim groups who participate in religious practices. This hostile environment can reinforce any fundamentalist beliefs that support extremism as a form of resistance against a host community that is not supportive. 
Almost all theoretical models point to the importance of the immigrant’s feelings of acceptance, respect, belonging, and recognition. They also show the culture of suspicion and surveillance and the feelings of disbelief and humiliation stimulate societal confusion, which may make young Muslim minorities more receptive of fundamentalist beliefs and extremism, and which can stimulate the search for inclusion and dignity. Islamism as a concept is presented as a response to an individual’s quest for belonging and respect, and as a way out of the frustrations of the immigrant’s feeling of being a second-class citizen living in a hostile Western society where Muslims have no place. 
In short, Europe stands now at crossroads that resulted from a turbulent combination of the need to remain faithful to European values, freedoms, and democratic principles, the preservation of freedom, justice, and the need to protect its citizens from new terrorism, the rise of right-wing leaders and parties demanding the opposite, and the return of “the politics of fear”.
In the United States and Europe, it is common for radical Islamists and radical populists to provoke fear of a real or a fake enemy, the matter that lays the groundwork for political change. Fear and hatred are passed from the second or third generation of young immigrants in the West to young people in the Middle East via the Internet and social media, which are used as tools to foster hatred against enemies, leading to dangerous, untraditional conflicts.
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