What if in the place of Stalin, the Soviet Union had instead been ruled by a Polish or German communist leader, either Jewish or non-Jewish. How would that change the Soviet Union's foreign policy?
Really don't think you're going to get a foreign national as the head of the USSR.
Ah. OP didn't say Polish or German origin, but you're right, this does make sense.I read OP´s question in the sense, that an ethnic German in the USSR (previous Russian Empire) (a Volga German for example) or Polish become head of the USSR/Communist Party General Secretary. Stalin was a Georgian after all. The early USSR loathed Nationalism as reactionary (even Russian nationalism). We could theoretically see an Armenian, Finnish, Baltic, Central Asian, Tatar or Chinese head of the Soviet Union as well (any plausible candidates) ? Lenin also had Tatar ancestors.