19 U.S.C. § 4432 - U.S. Code - Unannotated Title 19. Customs Duties § 4432. Establishment of preclearance operations

(1) to prevent terrorists, instruments of terrorism, and other security threats from entering the United States;

(2) to prevent inadmissible persons from entering the United States;

(3) to ensure that merchandise destined for the United States complies with applicable laws;

(4) to ensure the prompt processing of persons eligible to travel to the United States; and

(5) to accomplish such other objectives as the Secretary determines are necessary to protect the United States.