I've seen a video of Donn doing aikido - among the best I've ever seen. He had a 5th dan from Tomiki Kenji.
Uyeshiba's aikido is a highly weakened form of hand-to-hand combat. Aikido is essentially noncombative in nature. Further, the omission of atemi (strikes) from its techniques removes aikido from the category of practical hand-to-hand combat styles." "
Combat - Donn was, I believe, in combat
in the Korean war. That's what he meant by the word. Furthermore, when considering a martial art, he defined the term in a very circumscribed fashion - "martial" referred to the arts of war. Therefore, TSKSR was a "martial art" -in that the training was passed down thru a hereditary warrior caste, and the training methods were, allegedly, focused on the battlefield - albeit one in the past. Such disciplines as iaido, karate, aikido, etc. were civilian arts, not practiced as part of an exclusive warrior class for military aims.