Terrorism in Sri Lanka has been a highly destructive phenomenon during the periods of the Sri Lankan Civil War (1983–2009) and the first and second JVP insurrections (1971 and 1987–89, respectively). A common definition of terrorism is the systematic use or threatened use of violence to intimidate a population or government for political, religious, or ideological goals. Sri Lanka is a country that has experienced some of the worst known acts of modern terrorism, such as suicide bombings, massacres of civilians and assassination of political and social leaders, that posed a significant threat to the society, economy and development of the country. The Prevention of Terrorism Act of 1978 is the legislation, that provides the powers to law enforcement officers to deal with issues related to terrorism in Sri Lanka. It was first enacted as a temporary law in 1979 under the presidency of J. R. Jayewardene, and later made permanent in 1982.