Like the assaults in Paris last year, the March 22 terrorist attacks in Belgium prompted a wave of arrests and energized attempts by European authorities to disrupt the Islamic State and other jihadist operations. But arrests will not solve the intractable problem of radicalized Muslims bent on attacking Europe. Until the underlying issues that help drive radicalization on the Continent are addressed, authorities will be neutralizing only the immediate threat, not countering its root cause. In the meantime, jihadists will continue to pose a threat in Europe and elsewhere. Police and security forces across Europe arrested dozens of purported Islamic State operatives in the wake of the Brussels bombings . The arrests have not been limited to Belgium and France; they have also taken place in Germany, Italy and the United Kingdom.