Foreign relations 15 Politics and government 14 History 13 Leadership 7 Psychological aspects 7 World War, 1939-1945 7 Social aspects 6 War 5 Biography 4 Economic conditions 4 Military history, Modern 4 Campaigns 3 Congresses 3 Economic development 3 Personal narratives, American 3 Religious aspects 3 Security, International 3 Speeches, addresses, etc 3 United States 3 War and society 3 World War, 1914-1918 3 Case studies 2 Character 2 Christianity 2 Cultural policy 2 Defenses 2 Democracy 2 Eastern Front 2 Fighter pilots 2 International economic relations 2