Columbia subject headings:
Harvard subject headings:
International relations--History--20th century
International relations--History--21st century
Security, International--History.
Violence--History
World politics--20th century
World politics--21st century
Princeton subject headings:
International relations--History--20th century.
International relations--History--21st century.
Security, International--History.
Violence--History.
World politics--20th century.
World politics--21st century.