Terrorism -- Prevention. -- 26 Government policy -- 17 War on Terrorism, 2001-2009 17 Foreign relations -- 16 National security -- 13 Prevention -- 10 more ... September 11 Terrorist Attacks, 2001 9 Islam 8 Politics and government -- 8 Religious aspects -- 8 Prevention 7 Islamic fundamentalism 6 Terrorism 6 Civil defense -- 5 History -- 5 Intelligence service -- 5 Security measures 5 Civil rights -- 4 Jihad 4 Terrorists -- 4 Aeronautics, Commercial -- 3 Emergency management -- 3 Evaluation. -- 3 Islamic fundamentalism -- 3 Political aspects -- 3 Psychological aspects 3 Security measures -- 3 Terrorists 3 Hijacking of aircraft -- 2 less ...