Terrorism can be defined as (a) indiscriminate military violence or as (b) indiscriminate military violence by non-state organizations such as revolutionary movements or resistance or, as it is usually understood, as (c) use of terror as a political or military instrument. Because of the disagreements over who is a terrorist, there has been only feeble international cooperation on dealing with terrorism.
Terrorism is a socially constructed notion that is continuously renegotiated at the political level. It is almost a truism that one person's terrorist is another person's freedom fighter. Terrorism is generally defined as the symbolic use of actual violence, for political reasons, against non-military targets. By symbolic use, scholars of terrorism suggest that terrorism is successful when its message reaches a large public, much larger than the circle of those actually harmed by it.