Terrorism Terrorism -- 61 Prevention 26 World politics -- 13 Prevention -- 12 Terrorists 10 Security, International 8 more ... Political violence 7 History 6 Forecasting 5 Radicalism 5 Terrorists -- 5 War on terrorism, 2001- 5 Weapons of mass destruction 5 Foreign relations -- 4 Government policy -- 4 International cooperation 4 International relations 4 September 11 Terrorist Attacks, 2001 4 Violence 4 Fanaticism 3 Foreign relations 3 Globalization 3 Government policy 3 Hijacking of aircraft 3 National security -- 3 Security measures 3 War on Terrorism, 2001-2009 3 Aeronautics, Commercial -- 2 Conflict management 2 less ...