SNAFU is an acronym for, ‘Situation Normal, All Fucked Up’.

Modern definition
Snafu v. [sna-foo] [1940s+] (orig. US milit.)
To throw (a situation) into chaos.
adj. snafued
To mess up, to go wrong, esp. in a complex, elaborate manner.

Snarl, bedlam, tumult, disarray, disorder, confusion, mess, foul-up.

SNAFU, which stands for the sarcastic expression: ‘Situation Normal, All Fucked Up’ is a well-known example of military acronym slang. It means that the situation is bad, but that this is a normal state of affairs. The acronym is believed to have originated in the United States Marine Corps during World War II. SNAFU is a close relative of FUBAR (‘Fucked Up Beyond All Recognition’), which also dates from World War II.