Employee means an individual who is under the jurisdiction of a chief of mission to a foreign country as provided under section 207 of the Foreign Service Act of 1980. (22 U.S.C. 3927) and who is -
(1) An employee as defined by section 2105 of title 5, United States Code;
(2) An officer or employee of the United States Postal Service or of the Postal Rate Commission;
(3) A member of a uniformed service who is not under the command of an area military commander, or
(4) An expert or consultant as authorized pursuant to section 3109 of title 5, United States Code, with the United States or any agency, department, or establishment thereof; but is not a national or permanent resident of the foreign country in which employed.