That would be Walter Christie, an American. The T-34 was a slightly modified Christie design with a French (Hispano-Suiza) diesel engine. The Christie variant that the US made was significantly different because the Army insisted on a number of changes - which turned out to be a really bad idea. Oh well.
No kidding. That's interesting. I don't want to credit Stalin for making the right decision since he probably purged the best Russian minds the same way he purged his own military leadership.
I also made a mistake about the "F-111" which should be "F-117". I think it was from Russian research on constructing an aircraft of certain angles to reduce its radar profile.