Do you consider Transformers Japanese or American?

I personally consider it American. Well sure the idea originated in Japan, but it's the person or company that makes the idea popular and successful that really gets the credit for it. Transforming cars have been around for many many years. However, once hasbro got and molded the idea, they really popularized it. The idea may have roots in Japan, but it's technically American, as the brand was popularized and I believe patented in America. So it's techinically American, but what do you consider it.