Detailed answer:

The only car "ALLOWED" to be federally imported is the 1995 GTR or any car 25 years old. If your car isnt one of those 2, its illegal at the FEDERAL LEVEL.

State wise, every state has loop holes. Georgia you cannot Register a Japanese title at all IIRC they recently passed a law that doesnt allow the shorter VIN to be transferred from another state either.

The only thing you can do, is illegal and gray market. You can buy a totalled/scraped car of the same year, swap vin an title and crush the other car. Not legal by any means, but its been done