Terrorism is broadly defined as the use of violence against non-combatants to achieve political or ideological aims, though no universal definition exists due to its politicized and emotionally charged nature. The term originated during the French Revolution's "Reign of Terror" under the Jacobins, but gained worldwide currency in the 1970s through groups like the PLO, IRA, and ETA, and became globally prominent after the September 11 attacks in 2001. Modern terrorism often targets densely populated public areas—such as transportation hubs and tourist attractions—to instill widespread fear and manipulate policy, with the Global Terrorism Database recording over 61,000 incidents and at least 140,000 deaths between 2000 and 2014. Perpetrators range from left-wing and right-wing groups, nationalists, and religious organizations to ruling governments, with state terrorism—involving massacres, genocides, and torture—proving deadlier than non-state terrorism. The definition remains highly contested; as Harvard law professor Richard Baxter noted, the term is "imprecise" and "serves no operative legal purpose," highlighting the double standards and emotional charge surrounding its application.