I think it's from an old video game, at least that's what I remember from a random convo about the name a year or so ago. Don't quote me on that tho.
However it is nonsensical. It was originally chosen to talk about/make fun of japanophiles right in front of them/around them without them knowing.
But of course it didn't last long as too many people used it/became well known and some sects adopted it as a title.. much like some proudly carry the title "otaku" now a days.
EDIT: And I know it's hard to track these things and a lot of sites like to take credit for stuff that wasn't them, but I was around during its conception and 4chan does deserve credit for it.