National security 645 Security, International 323 Foreign relations 285 Thesis 280 Military policy 225 Dissertations, Academic 206 Politics and government 160 Terrorism 125 History 122 Security measures 120 Defenses 102 World politics 101 Prevention 99 Congresses 97 Armed Forces 88 Computer security 88 International relations 80 Strategic aspects 73 Computer networks 55 Government policy 54 United States 53 Law and legislation 39 Arms control 38 Military relations 37 Intelligence service 35 Internal security 33 Nuclear weapons 33 Strategy 33 International cooperation 30 Pacific Area 30