National security -- 32 Terrorism -- 15 Prevention. -- 8 Foreign relations -- 7 Military policy 7 World politics -- 6 War on Terrorism, 2001-2009 5 more ... Government policy -- 4 Intelligence service -- 4 Civil defense -- 3 Defenses 3 Foreign relations 3 Politics and government -- 3 Prevention 3 Security measures 3 Security, International 3 September 11 Terrorist Attacks, 2001 3 United States 3 International relations 2 National security 2 Security Management 2 Terrorism 2 War (International law) 2 Air power -- 1 Autobiographies 1 Biographies 1 Civil defense 1 Economic aspects -- 1 Economic development 1 Emergency management -- 1 less ...