Like you I always buy British whenever there is an equivalent product, however I would never buy anything made by Nissan in Washington....ever.
There you go, and my reasons are personal, and stem back to a time long long ago, when I was involved in factory automation in my day to day job.
I'd rather walk, and I'll not buy a Datsun as long as there is breath in my body, beside that, as it is an alien company, the profits are siphoned out of the local economy straight back to Japan.
Brian