Green’s Dictionary of Slang

Foggy Bottom n.

also Foggy Butts
[derived both f. the name of an area of Washington, D.C., and f. the ‘foggy’ obfuscations produced by its bureaucrats]

(US) the US State Department.

[US]Sat. Eve. Post 29 July 60: Foggy Bottom, as the new State Department Building is known [HDAS].
A. Schlesinger Jr A Thousand Days n.p.: In addition to the usual defects of Foggy Bottom prose, the paper was filled with bad spelling and grammar [R].
[US]Time 19 Oct. 17: A Christmas card she mailed out last winter was a two-page tirade against her Foggy Bottom enemies.
[US](con. 1945) E. Thompson Tattoo (1977) 325: Can you imagine a guy like that as President? President Foggy Butts. The Great I Am!
[US]H. Rawson Dict. of Invective (1991) 289: Foggy Bottom, a disparaging nickname for the U.S. State Department.
[US]Wall Street Journal 13 Oct. 🌐 While official policy was coziness with the House of Saud and Foggy Bottom was dominated by Arabists, there was some degree of tension.