World politics -- Periodicals 2 20th century 1 Balance of power 1 COVID-19 (Disease) 1 Foreign relations -- 1 History 1 more ... History -- 1 International -- 1 International competetition 1 International relations 1 International relations -- 1 Metropolitan areas -- 1 Military art and science -- 1 Military history, Modern -- 1 Periodicals -- 1 Political aspects 1 Psychological aspects 1 Sociology,urban 1 Urban climatology 1 less ...