Editor’s Note: Buck Sexton is a political commentator for CNN and host of “The Buck Sexton Show” on TheBlaze. He was previously a CIA counterterrorism analyst. The opinions expressed in this commentary are his.

Story highlights

More than 30 people were killed and hundreds wounded in terror attacks in Brussels on Tuesday

Buck Sexton: This nightmare is not over for Belgium, nor for the rest of Europe

CNN  — 

The physical and psychological scars of the November 13 terrorist attacks in Paris were still healing when Belgium was hit with its own devastating jihadist massacres on Tuesday. The arrest last Friday of Salah Abdeslam seemed to end one chapter of the ongoing threat, but instead of disrupting terrorist planning, it may have kicked the hornet’s nest and accelerated an attack.

Now the Islamic State of Iraq and Syria has claimed credit for yet another atrocity, this time in an airport and a metro station in Belgium, killing more than 30, shattering hundreds of lives, and raising concerns that more terrorist attacks like it are inevitable.


Buck Sexton

The truth is, this nightmare is not over – not even close. Not for Belgium, nor for the rest of Europe.

This is certainly true in an immediate sense, as there is a manhunt underway in Belgium. Surveillance footage from Brussels’ international airport shows a third individual who accompanied the two suicide bombers believed to have blown themselves up in the departure area. Once again, Belgian security forces are engaged in a sweeping dragnet, and further raids are to be expected in neighborhoods of Brussels that have become increasingly infamous for their radicalized residents.

One of those suspected local extremists, Abdeslam, may still have been operational while on the run, warned Belgian Foreign Minister Didier Reynders at the weekend. That raises the question of whether he was involved in the planning of Tuesday’s attack. If a high-priority target like Abdeslam could not only evade law enforcement for months, but actively plot another round of attacks, it would be a stinging indictment of the security services in Belgium. Perhaps to help turn things around, lawmakers there will decide it really is time to allow nighttime anti-terror raids on private homes.

But in the aftermath of this latest attack, many of the questions that are being asked – why is Brussels such a jihadist hotbed? How many more cells are active there? – are simply too narrow. Europe’s terrorism problem is much larger than jihadists in Belgium or France. They are the first two EU countries believed to be hit by ISIS in mass casualty attacks, but they will not be the last. In fact, the more we learn about ISIS’ capabilities and intentions, the clearer it becomes that the Islamic State’s terror war will expand past the borders of these two states.

And while Islamic terrorism is nothing new to Europe, the current circumstances for the continent are particularly dire for two reasons: ISIS and the migrant wave.

ISIS has recruited thousands of young Muslim men from European countries to the battlefields of Iraq and Syria. Those who are not killed, or choose not to stay, often return home as battle-hardened, committed terrorists. They also possess strong “tradecraft”– skills such as evading detection, communicating securely, acquiring and assembling material for explosives and plotting complex attacks.

Once they return home, these veteran jihadis have a force-multiplier effect within the radicalized communities that exist in every European state with a marginalized Muslim minority. They connect with already disaffected Muslim men, magnify the extremism of their views, and then weaponize them into actual jihadis. One knowledgeable bomb-maker can make explosive devices out of household chemicals for a dozen would-be suicide bombers; one ISIS member trained in counter-surveillance can teach a whole cell how to stay a step ahead of security forces. The returning jihadis aren’t just revered for their experiences in Syria – they put them to use in order to expand the conflict and bring it home to Europe’s front door.

This phenomenon of ISIS as the training ground for a whole new generation of European jihadis creates an enormous risk to a slew of EU countries. But there is an additional challenge: the migrant crisis.

The carnage of the Syrian civil war, the brutality of ISIS and Bashar al-Assad’s regime, and the sense of hopelessness across much of the Middle East has created an unprecedented wave of migrants to Europe over the last 12 months – well over a million in 2015 alone.

Many of these new entrants into Schengen Agreement countries, whose sheer numbers have overwhelmed the EU’s ability to process refugees in any meaningful way, are young Muslim males. Meanwhile, counterterrorism services are also completely overwhelmed by the volume of high-threat cases. The result has been a huge opportunity for ISIS to infiltrate into the heart of Europe with elite operatives. It seems to have already done so, with officials saying last year that two of the November 13 attackers took the “migrant route.” It would defy logic for ISIS to bypass this wide-open opportunity.

Given these two factors – ISIS providing a launch pad for jihad, and the huge influx of young Muslim males into Europe – more major terrorist attacks are a near certainty. And based on these dynamics, the two countries aside from France and Belgium that seem to be at highest risk for the next strike are Germany and the United Kingdom.

Germany alone has let in close to a million refugees. As precautions against attack, it has had to take dramatic action already, including shutting down a soccer game due to a credible threat, and engaging in major anti-terrorism raids. Britain, of course, has always been a favorite target of the jihadists. It is, after all, a close U.S. ally that is involved in the anti-ISIS air campaign, and ISIS has recently stated in its propaganda that the UK will suffer “harder and more bitter attacks” than Brussels. The Brits should be on high alert.

Recognizing the scale and scope of the threat is a necessary first step, but it is certainly not a strategy to thwart any future attacks. The painful truth is, there are no readily apparent plans to counter the jihadist threat in Europe. What we do know is that the enemy is already inside the gates, they are dedicated, ruthless, and able to hide among the masses. Many are moving around with impunity and outstripping the ability of the security forces to monitor them. With all these factors in play, the next major attack on European soil is a question of when, not if.

Sadly, for many Europeans, what feels like a daunting challenge for law enforcement today may start to feel like a struggle for the very existence of their free societies in the not-too-distant future.

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