Nothing new. Germany has always been the home of terror groups. American bases have always been a target. I remember the Red Army Faction in West Germany when I was stationed there. We had to QRF to the ammo depots that still had chemical munitions in them and be on alert for attacks on American holidays and terror anniversaries.
MPs in full combat gear patrolled my high school in May and June of 72 because of Baader Meinhof.