NEW YORK – What possessed the young French Muslim Mohammed Merah to murder three Jewish schoolchildren, a rabbi, and three soldiers, two of them fellow Muslims? What possessed another man, Anders Breivik, to gun down more than 60 teenagers in a Norwegian summer camp last year? These murder sprees are so unusual that people demand explanations.To call these killers "monsters,” as some were quick to do, sheds little light on the problem. They were not monsters; they were young men. And to dismiss them as madmen is equally evasive. If they were clinically insane, nothing more would need to be explained.Two accounts, both broadly socio-political, stand out. One was put forward by the controversial Muslim activist Tariq Ramadan. He blames French society. More specifically, he blames the fact that young Frenchmen of Muslim origin are marginalized on the grounds of their faith and the color of their skin.Even though these people have French passports, they are treated as unwanted foreigners. When French President Nicolas Sarkozy, himself the son of immigrants, says that there are too many foreigners in France, he drives young men like Merah farther into a corner. A tiny minority of such men might lash out in desperation.The other explanation, favored by Sarkozy, takes Merah at his word. He said that he was protesting French military operations in Muslim countries and avenging the killing of Palestinian children. He wanted to bring down the French state as an Islamic holy warrior. He was inspired by al-Qaeda. So why not believe him? Hence Sarkozy’s decision to arrest other Muslim men suspected of Islamic extremism and bar certain imams from attending a religious conference in France.Those who view Islamic extremism as the problem also tend to hold up young killers like Merah as examples of failed integration. They never became sufficiently French. Immigrants must be forced to share "Western values.”Although no one would argue that Anders Breivik is insufficiently Norwegian, he, too, could be taken at his word. The rhetoric of xenophobic demagogues appears to have convinced him that he had to kill the children of the social-democratic elites in order to protect Western civilization against the dangers of multiculturalism and Islam. His murders were the extreme result of dangerous ideas.Neither explanation is entirely wrong. Many young Muslims feel unwanted in their countries of birth, and extreme language, whether used by Islamists or their opponents, helps to create an atmosphere conducive to violence.But both Ramadan and Sarkozy are too simplistic, for they reduce extraordinary murders to single explanations. Even when they are faced with rejection, most young Muslim men do not become mass murderers. Merah is too anomalous to serve as a typical example of anything, including racial or religious discrimination.Far from being a religious fanatic, Merah grew up as a petty criminal with no interest in religion. The appeal of Islamist extremism may have been its glorification of violence more than any religious content. He enjoyed watching jihadist videos of beheadings. He also tried to join the French army and the Foreign Legion. The army turned him down because of his criminal record. If the French wouldn’t have him, he would join the holy warriors: anything to give him a sense of power and an excuse to indulge his violent impulses.Many young men are drawn to the fantasy of violence; far fewer feel the need to act it out. Ideology can serve as an excuse or justification, but it is rarely the main source of individual acts of brutality. Murder sprees are more often than not a form of personal revenge – losers wishing to blow up the world around them, because they feel humiliated or rejected, whether socially, professionally, or sexually.Sometimes, the killers appear to lack any excuse at all, as in the case of Eric Harris and Dylan Klebold, who in 1999 shot 12 fellow-students and a teacher at their high school in Columbine, Colorado. In that case, people blamed the sadistic video games and movies that the killers had been watching. Still, most enthusiasts of this type of entertainment do not actually go out and kill people.Breivik had fantasies of being a knight fighting the enemies of the West. Merah imagined that he was a jihadi. Who knows what the Columbine killers thought they were doing. But the reasons why they killed lie within them, and cannot be principally attributed to the entertainment or other materials that they consumed.Banning such materials has an aesthetic appeal, to be sure, and public figures who preach violence should always be condemned. Hate speech and violent ideology are not irrelevant. But to make too much of them in cases such as those of Merah or Breivik can be misleading.Censorship is unlikely to solve the problem. Banning Hitler’s Mein Kampf or forbidding the display of Nazi symbols has not stopped neo-Nazis in Germany from murdering immigrants. Suppressing violent pornography will not get rid of rapists or high-school killers. Preventing demagogues from ranting about Muslims or multi-culturalists will not deter a future Anders Breivik. And barring radical imams from entering France won’t stop another Merah from going on a murderous rampage.In fact, to compare Merah’s savage deeds to the killings of September 11, 2001, as Sarkozy has done, is to give the killer too much credit. There is no evidence that he is part of any organized group, or in the vanguard of a revolutionary movement. Using his case to stoke fear of an Islamic threat to society might make electoral sense for Sarkozy. But provoking fear is seldom the best recipe for avoiding further violence. On the contrary, it is more likely to fuel it.Ian Buruma is Professor of Democracy and Human Rights at Bard College, and the author of Taming the Gods: Religion and Democracy on Three Continents.Copyright: Project Syndicate, 2012.www.project-syndicate.org