A non-aggression pact is not an alliance, nor does it make an ally. Hitler fundamentally hated the communists, but was also desperate to prevent the USSR from joining the war. Stalin also fundamentally hated the Nazis.
Jointly dividing Poland and having a military parade there is not an alliance?
Providing secret base for U-boats - just a pact, not an alliance?
Which fits the duck allegory perfectly, since it refers to something that is not actually a duck.
https://www.mirror.co.uk/usvsth3m/you-know-phrase-if-looks-5...