Government policy Terrorism 71 Prevention 43 National security 26 Foreign relations 16 History 12 Nuclear weapons 11 Human rights 8 Thesis 8 War on terrorism, 2001- 8 Dissertations, Academic 7 Emigration and immigration 7 Military policy 7 Politics and government 7 United States 7 Marine resources 6 Nuclear nonproliferation 6 Bioterrorism 5 Congresses 5 Economic conditions 5 Intelligence service 5 International cooperation 5 Political aspects 5 Climatic changes 4 Cross-cultural studies 4 Environmental policy 4 Law and legislation 4 Psychological aspects 4 Case studies 3 Civil rights 3