As Infiniti is owned by Nissan and is therefore Japanese, that is if you want to follow one method of defining the country. From Wikipedia, "Infiniti is the luxury vehicle division of Japanese automaker Nissan. Infiniti officially started selling vehicles on November 8, 1989 in North America."
You need to add the US to Infiniti, Acura, and Lexus since that is where they originally began selling cars.