Franklin Roosevelt actually said...
Seamen whose occupational status as such is found to be bona fide, entering the ports of the United States solely in the pursuit of their calling as seamen, may be admitted temporarily in the discretion of the Secretary of Labor and under regulations prescribed by the Secretary without passports or visas if arriving in the United States under the following circumstances.
Context
Executive Order 7797—Documents Required of Bona Fide Alien Seamen Entering the United States
01/25/1938