Terrorism 34 September 11 Terrorist Attacks, 2001 23 Prevention 19 Foreign relations 15 Influence 9 Politics and government 9 Government policy 8 United States 8 National security 7 War on terrorism, 2001- 6 Islamic fundamentalism 5 War on Terrorism, 2001- 5 War on Terrorism, 2001-2009 5 Intelligence service 4 Military policy 4 Defenses 3 Forecasting 3 International relations 3 Iraq War, 2003 3 Iraq War, 2003- 3 Islam and politics 3 Qaida (Organization) 3 Security, International 3 Thesis 3 World politics 3 Civil defense 2 Civil rights 2 Detention of persons 2 Dissertations, Academic 2 Economic policy 2