Richard Nixon actually said...
It is, of course, in the interest of the United States that United States citizens who participate in the activities of NATO, SEATO, and CENTO as direct hire employees of the civil or military agencies of those organizations be reliable, trustworthy, of good conduct and character, and of complete and unswerving loyalty to the United States.
Context
Executive Order 11633—Security Clearance Program for United States Citizens Employed Directly by the North Atlantic Treaty...
12/02/1971