19 USC 2433 – United States personnel missing in action in Southeast Asia
(a) Penalty for noncooperating countries
Notwithstanding any other provision of law, if the President determines that a nonmarket economy country is not cooperating with the United States—
(1) to achieve a complete accounting of all United States military and civilian personnel who are missing in action in Southeast Asia,
(2) to repatriate such personnel who are alive, and
(3) to return the remains of such personnel who are dead to the United States,
then, during the period beginning with the date of such determination and ending on the date on which the President determines such country is cooperating with the United States, he may provide that—
(A) the products of such country may not receive nondiscriminatory treatment,
(B) such country may not participate, directly or indirectly, in any program under which the United States extends credit, credit guarantees, or investment guarantees, and
(C) no commercial agreement entered into under this subchapter between such country and the United States will take effect.
(b) Exception
This section shall not apply to any country the products of which are eligible for the rates set forth in rate column numbered 1 of the Tariff Schedules of the United States on January 3, 1975.