Prevention Terrorism 84 Government policy 26 National security 20 United States 18 September 11 Terrorist Attacks, 2001 11 Foreign relations 9 War on terrorism, 2001- 8 Civil defense 7 History 6 Intelligence service 6 Politics and government 6 Cyberterrorism 5 Emergency management 5 Islamic fundamentalism 5 Civil rights 4 Law and legislation 4 Nuclear terrorism 4 Security measures 4 War on Terrorism, 2001- 4 Bioterrorism 3 Counterinsurgency 3 Defenses 3 Internal security 3 Islam 3 Military policy 3 Religious aspects 3 Safety measures 3 Special operations (Military science) 3 War on Terrorism, 2001-2009 3