Government policy Security measures Prevention 5 National security 4 Terrorism 3 Computer crimes 2 Computer networks 2 Computer security 2 Cyberspace 2 Cyberterrorism 2 Disasters 2 Emergency management 2 Hazard mitigation 2 Information warfare 2 Infrastructure (Economics) 2 Risk management 2 Threats 2 Airports 1 Data encryption (Computer science) 1 Electronic surveillance 1 Political aspects 1 Risk assessment 1 Telecommunication 1 Wiretapping 1