The new Tundra is almost entirely made in the USA. The engines are even built in Georgia IIRC. That's more than the F150 or Silverado can boast. So it wouldn't surprise me if the diesels would be built here as well. Especially since Toyota would have to build something to compete with the big diesels. I'm not aware of any 1+ ton engines they produce anywhere else. That being said I know very little about Toyota Diesels.
"-1988 Red Hilux Standard frame, X-tra cab, locked F&R, 5.29's, 35" tires and a SAS. In Moab
"-1988 Hilux, 1999 3.4L, Supercharged, 2.1" URD pulley, URD 7th injector, 2 1/2" Magnaflow exhaust, TO DO: lift, locker.
"-1987 Super Beast
"Did you know the IFS was designed by Hitler himself to make the life of 4WD owners tough? Yeah, it's true, he saw a vision of the Devil and he told him to do it." -DaveInDenver