French police patrol the entrance of the Christmas market in Strasbourg on Dec. 20. (Patrick Hertzog/Agence France-Presse)

In recent years, Europe has been rocked by a series of catastrophic terrorist attacks either organized or inspired by Islamist groups. The attacks have left the continent fearful and divided, fundamentally changing the political discourse about Islam and immigration.

This week's incidents — the assassination of the Russian ambassador to Turkey and a deadly truck rampage at a Christmas market in Berlin — seem likely to compound the problem. The Islamic State claimed responsibility for the Berlin attack on Tuesday, and the gunman who killed diplomat Andrei Karlov shouted a slogan used by Islamists after he fired his shots. Shortly after the attacks, President-elect Donald Trump tweeted that the problem “is only getting worse” and that the “civilized world must change [its] thinking.”

The incoming Trump administration is at odds with many experts when it comes to Islam and extremism. But some share his pessimism, if nothing else. In the latest issue of Perspectives on Terrorism, an academic journal published by the Terrorism Research Initiative, Thomas Hegghammer offers a worrying prognosis for the long-term future of Islamist extremism in Europe: things will probably get worse.

Hegghammer is a senior research fellow at the Norwegian Defense Research Establishment (FFI) in Oslo, and he is often cited as a leading expert on violent Islamist extremism. In his article, he notes that while there has long been terrorism in Europe, there has been an undeniable surge in Islamist-extremism-related activism and violence over the past few years. To quote just one indicator Hegghammer cites, 273 people were killed by “jihadi” attacks in Europe between 2014 and 2016 — more than the all previous years combined.

In the short term, Hegghammer suggests that a variety of countermeasures, including increased budgets for security services and attempts to root out recruitment networks, will likely produce a decline in activity from Islamist extremists in the next two to five years. But he sees little reason to be optimistic in the long term, writing that there are a number of trends that “point to a future with even larger radicalization and terrorism challenges than today.”

First, there is the growing number of economically underperforming Muslim youths in Europe. This is traditionally a pool from which extremist groups recruit, and Hegghammer writes that this population looks set to continue to grow dramatically thanks to immigration and higher birth rates. Entrenched economic disadvantages will likely stop many young Muslims from gaining the full benefits of modern European societies.

The second, more important trend is the growing number of “jihadi entrepreneurs” — returned foreign fighters and other activists — who could inspire and recruit a new generation of European extremists. Hegghammer conservatively estimates there are now at least 2,000 radical Islamists in Europe with foreign fighter experience, time in prison, or both. While some may turn away from jihadism in the future, a small proportion will not.

The third and fourth factors relate not just to Europe, but to the broader world. Hegghammer suggests that persistent conflicts in the Middle East, North Africa and South Asia look “set to supply European jihadis with both rallying causes and training opportunities for the foreseeable future, as it has in the past.” Many experts believe that the conflict in Syria may still have a long way to go and that groups like the Islamic State will be very hard to fully defeat. The group could be training and blooding potential European attackers for years to come.

Compounding this problem is the final factor: the Internet. The Internet has considerable benefits for extremist groups, Hegghammer suggests, serving as a tool for “propaganda distribution, recruitment, fundraising, reconnaissance, and operational coordination.” The rise of encrypted communications and social media have made it harder for authorities to keep up.

If these trends continue, Hegghammer predicts that Europe could well see higher levels of Islamist extremism activity in the next five to 15 years depending on how European authorities are able to respond to new threats, this could well mean more terrorist attacks.

It's a worrying prediction, but things can change in ways that aren't foreseeable right now. Hegghammer admits it's certainly possible that any one of these trends could shift and change the scenario completely. Governments may prove more adept at fighting extremism and policing extremist networks than he has predicted, or there may be a broader shift in the Islamic world that draws the already tiny minority of Muslims who might engage in terrorism away from it.

Hegghammer also sees how the debate about the future of Islamist extremism could have a negative affect, too. As he notes, even terrorism scholars themselves have a “well-earned reputation” for alarmism, which can bleed over into the broader political debate. And if fears and anti-Muslim xenophobia shift into terrorism against Muslims in Europe by the far right, he writes, things will become far worse for everyone.

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