National security -- Terrorism -- Prevention. -- 10 Prevention -- 5 Government policy -- 4 War on Terrorism, 2001-2009 4 Civil defense -- 3 more ... Intelligence service -- 3 Foreign relations -- 2 International cooperation 2 Law and legislation 2 Military policy 2 Politics and government -- 2 Prevention 2 Security measures 2 September 11 Terrorist Attacks, 2001 2 Air power -- 1 Civil defense 1 Civil rights -- 1 Defenses 1 Deterrence(strategy) 1 Droit 1 Droits de l'homme (Droit international) 1 Emergency management -- 1 Evaluation. -- 1 Foreign relations 1 Government policy 1 Governmental investigations -- 1 Harbors -- 1 History -- 1 less ...