The correct answer to this open question is the following.
The term best describes attacks on crowds of ordinary people in order to create fear for a political objective is "terrorism."
Governmental authorities define terrorism as a strategy to produce fear. These violent attacks of terrorists on innocent crowds want to generate fear to pressure governments to accept terrorist demands. There have been many terrorist attacks in recent times after September 11, 2001, attacks in New York City. There have also been attacks in the London Subway, in Paris, France, and other European countries. Most of the terrorist groups or cells have operations in the territories of the Middle East.
