Prevention -- National security -- 8 Terrorism -- 7 Congresses 6 Congresses -- 5 Emergency management -- 2 Security measures -- 2 more ... Computer networks -- 1 Cyberspace -- 1 Cyberterrorism -- 1 Defenses -- 1 Emergency managemen 1 Epidemics -- 1 Government policy 1 Influenza -- 1 International cooperation -- 1 Maritime terrorism -- 1 Merchant marine -- 1 Political planning -- 1 Political violence -- 1 Prevention 1 Security, International -- 1 congresses 1 less ...