Columbia subject headings:
Civil war--Yemen (Republic)
National security--Saudi Arabia.
Saudi Arabia--Foreign relations--Yemen (Republic)
Yemen (Republic)--Foreign relations--Saudi Arabia.
Yemen (Republic)--Politics and government--21st century.
Harvard subject headings:
Battles--Yemen (Republic)
Bombing, Aerial--Yemen (Republic)
National security--Arab countries
National security--Saudi Arabia.
Saudi Arabia--Foreign relations--Yemen (Republic)
Princeton subject headings: