As more foreign fighters return from the ISIS battlefields to their home countries and face possible prosecution and imprisonment, the European Union continues to wrestle with how to deal with Islamic radicalization within its prisons.
American policymakers need to pay attention because it's a challenge we face, too.
"We found a lot of people that maybe weren't convicted on terror-related charges were radicalizing in the prison systems," U.S. Rep. Mike McCaul said last month. "I think the Bureau of Prisons needs a program to ensure that radicalization is not taking place because it is."
A recent investigation by Spanish counter terrorism officials uncovered a jihadi recruitment network operating inside 17 of its prisons. The group recruited and radicalized new inmate converts and planned to carry out several attacks when some of its members were released.