Terrorism experts have long warned of the danger posed by young men like Anis Amri, the suspected perpetrator of the Berlin Christmas Market massacre, shot dead in Milan this morning. That threat does not, however, come from ISIS operatives hiding among the thousands of refugees fleeing the Syrian Civil War. Like the mastermind of the 2004 Madrid bomber, Amri was a North African radicalized in a European prison.
To the relief of many Germans, especially Angela Merkel, Amri did not arrive with the more than 900,000 refugees her government has taken in over the past year. The Tunisian man came to Italy in 2011 to seek his fortune. He soon became involved in petty crime and spent time in an Italian prison, where, according to his father, he was radicalized by other inmates. Upon his release in 2015, he traveled to Germany, where he sought asylum. The authorities denied his request because of his suspected connections to terrorists, but they failed to deport or even detain him.
Amri was not the first young Muslim man to follow this path to destruction. Jamal Ahmidan was a Moroccan-born drug dealer who immigrated to Spain. Like Amri he was radicalized in prison. He was a major figure in planning and carrying out the 2004 Madrid Train bombings. He and two other suspects blew themselves up in their apartment when cornered by Spanish police.
Terrorist analysts have long warned of the threat posed by angry young men. New arrivals to Europe, away from home, family, and friends, are particularly vulnerable to terrorist recruitment, especially if they become involved in illegal activities. The prisons where some of them end up are not only universities of crime; they are schools for radicalization.
If countries are concerned about who they let in, they would do well to focus on unaccompanied young men, not because they are terrorists but because they are the demographic group from which so many terrorists are recruited. Intact families and women with children are less of a concern. Young men need not be categorically excluded, but they should be carefully screened, monitored and given the economic and social support that would make them less prone to radicalization. There must also be an efficient mechanism for detention and deportation of those denied asylum because of suspected ties to extremist groups.