Government policy Terrorism 86 Prevention 47 National security 27 Foreign relations 23 History 18 War on terrorism, 2001- 13 Nuclear weapons 11 Politics and government 10 United States 10 Thesis 9 Dissertations, Academic 8 Human rights 8 Military policy 8 Emigration and immigration 7 Intelligence service 7 Bioterrorism 6 Marine resources 6 Nuclear nonproliferation 6 Political aspects 6 September 11 Terrorist Attacks, 2001 6 Congresses 5 Economic conditions 5 International cooperation 5 Climatic changes 4 Cross-cultural studies 4 Environmental policy 4 Islam and politics 4 Jihad 4 Law and legislation 4