In "Atlas Shrugged" by Ayn Rand, the question "Who is John Galt?"
is answered towards the closing of the novel — John Galt is a man
disgusted that non-productive members of society use laws and guilt
to leech from the value created by productive members of society,
and furthermore even exalt the qualities of the leeches over the
workers and inventors. He made a pledge that he would never live
his life for the sake of another man, nor ask another man to live
for him, and founded an enclave, separate from the rest of the
country, where he and other productive members of society have
fled.
"Who is John Galt?" It is a reflection of their helplessness, as
the saying means "Don't ask important questions, because we don't
have answers."
Thanks to nicolo for the crackin' original cache container!
