Two simultaneous plot twists: First Stalin once again ignores the warnings from his spies, believing (correctly) that the western democracies would be completely mad to fight an even bloodier war when their performance in the recent one proved that they can't stomach the levels of meat grinding that's the norm on the Eastern front. Second when Unthinkable finally goes off it promptly faceplants immediately as the majority of the units (both enlists the bulk of officers) simply refuse to follow the insane orders to kick off another war immediately.
Thus the Western democracies just sulks off and tries to pass off everything as "just a prank bro" and Stalin, while reaping the propaganda coup, mostly "let it go" as he uses the time and breathing space to shore up internal issue and tighten his hold on Eastern Europe.