Prevention Terrorism Definition and introduction The difficulty in defining terrorism is in agreeing on a basis for determining when the use of violence (directed at whom, by whom, for what ends) is legitimate; therefore, the modern definition of terrorism is inherently controversial. The use of violence for the achievement of political ends is common to state and non-state groups. The majority of definitions in use has been written by agencies directly associated with government, and is systematically biased to exclude governments from the definition. The contemporary label of "terrorist" is highly pejorative-- it denotes a lack of legitimacy and morality. As a practical matter, so-called acts of terrorism or terrorism are often a tactic committed by the actors as part of a...