Will McCants and Chris Meserole use quantitative methodologies to explain why so many ISIS fighters come from France, Belgium, and Tunisia. Part of the answer lies in the French notion of secularism. They conclude, ” Among the countries that do not border Syria, the three highest-scoring were Tunisia, Belgium, and France. Each of them is Francophone. Each of them had a painful public debate about Islamic headdress in the year before the Syrian civil war began. And in the post-2014 period, each has suffered a major, mass-casualty terror attack carried out by Sunni extremists.” Check out this fascinating study at Chris Merserole’s blog.