Government policy -- Terrorism -- 35 Prevention -- 18 Foreign relations -- 15 Government policy 11 History -- 10 Nuclear weapons -- 9 more ... Economic conditions -- 8 Congresses -- 7 National security -- 7 Petroleum industry and trade -- 7 Politics and government 7 Politics and government -- 7 Prevention. -- 7 Case studies 6 Congresses 6 Economic policy 6 Economic policy -- 6 Case studies -- 5 Economic aspects -- 5 Emigration and immigration -- 5 Prices -- 5 Refugees -- 5 Terrorism 5 War on Terrorism, 2001-2009 5 Agriculture and state -- 4 Economic conditions 4 Environmental policy -- 4 Food supply -- 4 Industrial policy -- 4 less ...