What about folks living in Japan, who buy a camera there and then move to the US in less than a year? No warranty for them?
I can't tell you how this works with Nikon, but with Canon they have a something called an "international" warranty but it only *might* cover a person.
Here's how that works:
Suppose you live in the USA, but you're on a vacation in another country (it could be Japan but it could be anywhere) and you decide to buy a new camera (for whatever reason... your current camera broke, or you just decided you had to have that new camera you saw in the shop window.)
Normally Canon USA will only service a camera (warranty service or even paid service for the camera when it's outside of warranty) if the camera was imported into the USA
by Canon and nobody else (which makes it a "USA" model). But this creates a problem for people who buy cameras while out of the country.
So Canon's "international" warranty says that *if* you can actually *prove* that you were
physically in
that country when you bought that camera, *then* they don't consider it "gray market" and they'll go ahead and service it.
What they don't explain is how you "prove" this. Do you submit airline or hotel receipts with your name on them showing that you were in that country at the time of purchase? Did you have to mail in a special registration card with proof at the time of purchase? I don't know the answer.
I assume Nikon probably has a similar rule because they tend to match each other.
But what I can tell you is that *generally* speaking, neither Canon nor Nikon will agree to perform service on a camera that they consider to be "gray market" (meaning you got the camera imported into the country via someone else and it bypassed their normal import process for gear intended to be sold in this market.)
If you buy an "import" camera, you should generally treat it as a non-serviceable camera. Likely the only way you'll get it serviced is to find a private camera repair shop.