Term
|
Definition
March 23, 1953
April 2, 1955
Under Dwight D. Eisenhower |
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Term
|
Definition
April 2, 1955
September 1, 1956
Under Dwight D. Eisenhower |
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Term
|
Definition
September 1, 1956
January 7, 1957
Under Dwight D. Eisenhower |
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Term
|
Definition
January 7, 1957
June 24, 1958
Under Dwight D. Eisenhower |
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Term
|
Definition
June 24, 1958
January 13, 1961
Under Dwight D. Eisenhower |
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Term
|
Definition
January 20, 1961
February 28, 1966
Under John F. Kennedy, Lyndon B. Johnson |
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Term
|
Definition
April 1, 1966
December 2, 1968
Under Lyndon B. Johnson |
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Term
|
Definition
December 2, 1968
November 3, 1975
Under Richard Nixon, Gerald Ford |
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Term
|
Definition
November 3, 1975
January 20, 1977
Under Gerald Ford |
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Term
|
Definition
January 20, 1977
January 21, 1981
Under Jimmy Carter |
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Term
|
Definition
January 21, 1981
January 4, 1982
Under Ronald Reagan |
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Term
|
Definition
January 4, 1982
October 17, 1983
Under Ronald Reagan |
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Term
| LtCol Robert C. McFarlane |
|
Definition
October 17, 1983
December 4, 1985
Under Ronald Reagan |
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Term
|
Definition
December 4, 1985
November 25, 1986
Under Ronald Reagan |
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Term
|
Definition
December 2, 1986
November 23, 1987
Under Ronald Reagan |
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Term
|
Definition
November 23, 1987
January 20, 1989
Under Ronald Reagan |
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Term
|
Definition
January 20, 1989
January 20, 1993
Under George H. W. Bush |
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Term
|
Definition
January 20, 1993
March 14, 1997
Under Bill Clinton |
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Term
|
Definition
March 14, 1997
January 20, 2001
Under Bill Clinton |
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Term
|
Definition
January 22, 2001
January 25, 2005
Under George W. Bush |
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Term
|
Definition
January 26, 2005
January 20, 2009
George W. Bush |
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Term
|
Definition
January 20, 2009
Incumbent
Under Barack Obama |
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