Columbia subject headings:
Asia, Central--Foreign economic relations--United States.
Gas industry--Middle East.
Iran--Foreign economic relations--United States.
Middle East--Foreign economic relations--United States.
Petroleum industry and trade--Middle East.
United States--Foreign economic relations--Asia, Central.
United States--Foreign economic relations--Iran.
United States--Foreign economic relations--Middle East.
Harvard subject headings:
Asia, Central--Foreign relations--21st century.
Asia, Central--Politics and government--21st century.
Energy industries--Political aspects--Asia, Central.
Energy industries--Political aspects--Iran.
Energy industries--Political aspects--Middle East.
Geopolitics.
Iran--Foreign relations--21st century.
Iran--Politics and government--21st century.
Middle East--Foreign relations--21st century.
Middle East--Politics and government--21st century.
Russia (Federation)--Foreign relations--21st century.
Russia (Federation)--Politics and government--21st century.
United States--Foreign relations--21st century.
United States--Politics and government--21st century.
World politics--21st century
Princeton subject headings:
Asia, Central--Foreign economic relations--United States.
Gas industry--Middle East.
Iran--Foreign economic relations--United States.
Middle East--Foreign economic relations--United States.
Petroleum industry and trade--Middle East.
United States--Foreign economic relations--Central Asia.
United States--Foreign economic relations--Iran.
United States--Foreign economic relations--Middle East.