No, "Asian" is a race, "Japanese" is a nationality, which doesn't necessarily require one be Asian.

Ainu is a race, as are Yamato and Ryukyuan. Asian is a much bigger race, then we have nationalities. Sometimes Japanese is used to mean Yamato.

Also, see Han (ethnicity) and Chinese (nationality), where outside of China the latter is often used to mean the former.

Fair enough, and I'm sure that when Japanese nationalists talk about Japanese as a race, they probably mean Yamato, but that doesn't make it accurate to describe "Japanese" as a singular ethnic or racial identity.

It isn’t accurate but nor is it exactly wrong. The word is very contextual. Most nationalities can be construed into races, and many things we considered race today arose from nationalities a long time ago (in the long run they blend together).

Aren't there specific ethnic groups indigenous to Japan, that one might refer to collectively as the 'Japanese' regardless of nationality ?