Columbia subject headings:
Aeronautics, Commercial--United States--Safety measures.
Surface-to-air missiles--Government policy--United States.
Terrorism--United States--Prevention.
Weapons--Law and legislation--United States.
Harvard subject headings:
Aeronautics, Commercial--United States--Safety measures.
Surface-to-air missiles--Government policy--United States.
Terrorism--United States--Prevention
Weapons--Law and legislation--United States.
Princeton subject headings:
Aeronautics, Commercial--United States--Safety measures.
Surface-to-air missiles--Government policy--United States.
Terrorism--United States--Prevention.
Weapons--Law and legislation--United States.