 Complete the following phrase:  The perpetrators of acts of terrorism can be individuals, groups, or states. According to some definitions, clandestine or semi-clandestine state actors may carry out terrorist acts outside the framework of a state of war. The most common image of terrorism is that it is carried out by small and secretive cells, highly motivated to serve a particular cause and many of the most deadly operations in recent times, such as the September 11 attacks, the 