Columbia subject headings:
Europe--Foreign relations--United States.
United States--Foreign relations--Europe.
Harvard subject headings:
Armored vessels--United States.
Europe--Foreign relations--United States.
Foreign trade promotion--United States.
United States--Foreign relations--Europe.
Princeton subject headings:
Armored vessels--United States.
Europe--Foreign relations--United States.
Foreign trade promotion--United States.
United States--Foreign relations--Europe.