Terrorism is, in its broadest sense, the use or threatened use of violence (terror) in order to achieve a political, religious, or ideological aim. It is classified as fourth-generation warfare and as a violent crime. In modern times, terrorism is considered a major threat to society and therefore illegal under anti-terrorism laws in most jurisdictions. It is also considered a war crime under the laws of war when used to target non-combatants, such as civilians, neutral military personnel, or enemy prisoners of war.