Last week, a series of attacks took place in Paris that will radically change the way the European leadership views the extremist Muslim threat.But in actuality, members of radical Islamist groups have been carrying out terrorist attacks in Europe for more than a decade: The outspoken Dutch filmmaker Theo van Gogh was murdered in 2004, and the Islamic scarf controversy in France has been a hot topic since 1989. And this past year, a number of attacks by Muslim extremists took place in European cities: A British soldier was decapitated in London, French soldiers were killed in Montauban and Toulouse, and two car bombs wreaked havoc in Malmo, Sweden.Forty-four million Muslims live in Europe, according to data gathered by European research institutes. Four years ago, the official number of Muslims residing legally in Europe was 20 million. At the time, it was estimated that in 2019, 50 million Muslims living there, 20 million of whom would be illegal immigrants.According to forecasts, by the end of the century, there will be a clear Muslim majority.Muslim migration to Europe began right after the Second World War following two developments. The first was the relinquishment by European nations of overseas colonies and the granting of citizenship to residents of these countries, such as when France withdrew from Algeria. The second was growing industrialization for which European countries needed cheap. Because immigration policies were so liberal, and it was easy to receive citizenship, large numbers of Muslims from poor countries began arriving. A huge wave of Turkish nationals immigrated to Germany; Algerians, Moroccans and Tunisians immigrated to France; Libyans moved to Italy; and Lebanese made their way to Scandinavia. And then each family brought over dozens of extended family members and soon entire neighborhoods in major cities were populated almost solely by immigrants.Over the last few decades, European countries have encouraged multiculturalism – they did not realize the threat the rise of Islam in Europe beholds. The Europeans viewed their new Muslim neighbors as legitimate immigrants and assumed that they would soon acculturate to a Western way of life. But as we all know, this is not what happened. The exact opposite is true. The immigrants established their own neighborhoods, built mosques and independent Muslim schools.The birth rate among Muslims in Europe is three times the average. Amsterdam is expected to have a Muslim majority within a decade. Islam is already the second-most common religion, and Muslims make up 6 percent of residents in Europe. A new reality is settling in: entire neighborhoods where almost no non-Muslim can be found.Even the police don’t dare enter these streets. Religious fanatics have taken control of these neighborhoods where women cover themselves from head to toe and all the signs are in Arabic.The Muslim community has a plan to build super-mosques in every large city that will dwarf every church in the region.Many public schools in Belgium and Denmark provide halal food to all students. In the Amsterdam of yesteryear, the Dutch people were always very tolerant of gay and lesbians, but today homosexuals find themselves being repeatedly attacked by Muslims. In France, the Education Ministry has recommended that teachers refrain from assigning books that contain ideas that might be offensive to Islam, and they are prohibited from teaching about evolution and Darwinism.The history of the Shoah is almost not taught anymore in certain schools so as not to offend Muslim sensibilities. In the UK, Shari’a (Muslim) law has officially become part of the legal system. In certain neighborhoods in Paris, women are not allowed to walk around with their heads uncovered.According to surveys carried out in France, one-third of Muslims living there do not object to suicide attacks. And the British Centre for Social Cohesion has reported that one-third of Muslim university students in the UK are in favor of Islamic State.We must understand that Muslims do not move to a new place in order to mingle and integrate with the indigenous population.On the contrary – they come in order to change Western culture to be more like theirs: Dar al-Islam Islam is based on a totalitarian political ideology and a way of life that sets detailed rules for society and how individuals must comport themselves. Islam dictates every aspect of people’s lives, and does not tolerate anyone who deviates from the path.Democracy is not compatible with Shari’a law. There is no possibility for coexistence between European liberal values and Islamic culture.Europeans are just now finally beginning to wake up and realize that their dream of living in a heterogeneous culture that includes Islam cannot come true and that they are headed toward serious cultural and religious clashes.It is true that most Muslims in Europe are busy trying to survive and looking for work and ways to support their families. The radical terrorist cells are a small minority scattered throughout the continent. But to prevent these waves of terrorism from increasing, Europeans must carry out six steps: The first step is to understand that the enemy is alive and kicking in the poor and quickly expanding Muslim population centers.It is much easier to recruit activists from poor communities where unemployment is rampant. These populations much be mapped out and the dangerous extremist centers must be located and identified.Second, European countries need to pass legislation that will empower law enforcement authorities and the courts to thwart future activity and allow for the imprisonment of terrorists who have carried out subversive activity. This is the most effective way to prevent terrorist cells from forming in the first place.The third step is to form a unit to carry out intelligence gathering among problematic populations. The proper technological devices need to be utilized in order to gain a full picture of what is happening on the ground in real time.The fourth step is to build organizational and computerized platforms that would help the authorities employ personnel and technological devices in a professional manner.The fifth step is to increase intelligence cooperation and transparency among the various European Union intelligence agencies.The sixth and last step is to be able to distinguish between the “lone wolves” who carry out an attack as a personal act of revenge, who have no weapons or training, and the organized terrorist cells whose members are trained by jihadist organizations.The latter groups can be located with the help of human and computerized intelligence surveillance.The writer is a former brigadier-general who served as a division head in the Shin Bet (Israel Security Agency).Translated by Hannah Hochner.