Columbia subject headings:
Border patrols--United States.
Drug control--United States.
Illegal immigration--Government policy--United States.
Noncitizens--Government policy--United States.
Smuggling--United States--Prevention.
U.S. Border Patrol.
United States--Emigration and immigration--Government policy.
Harvard subject headings:
Border security--United States
Drug control--United States
Illegal immigration--Government policy--United States.
Noncitizens--Government policy--United States
Smuggling--United States--Prevention.
U.S. Border Patrol
United States--Emigration and immigration--Government policy
Princeton subject headings:
Border patrols--United States.
Drug control--United States.
Illegal aliens--Government policy--United States.
Smuggling--United States--Prevention.
U.S. Border Patrol.
United States--Emigration and immigration--Government policy.