Spanish authorities have arrested a Muslim cleric — whom the New York Times once praised for his efforts to fight radicalization within Germany’s Islamic community — for alleged ties to the Islamic State. Hesham Shashaa (aka Abu Adam), a 46-year-old Egyptian-Palestinian, was detained near Alicante in southeastern Spain on April 26 on charges of aiding the Islamic State, extolling terrorism and promoting Salafi-jihadism. The Spanish Interior Ministry said that Shashaa had facilitated the travel to Spain of Islamic State jihadists from Syria and Iraq by providing them with money, refuge and fake documents. Most recently, Shashaa had made arrangements for...