Khrushchev is the perfect example of a national leader whose image has changed in light of declassified information.
In the 1970s and 1980s, History classes taught me that the he was a vain, bellicose, unstable man who pounded his shoe on the table in the UN. His most famous quote was, "We will bury you." Even that is disputed now as a possible mistranslation of his actual words, which could be translated as "We will outlast you" or "We will attend your funeral."
(Notice the shoe on the table here :) )
In my Military History classes in the 1990s, with the benefit of the revelations of Khruschev telling Kennedy about the Soviet tactical nukes in Cuba, he was portrayed as a man who put on a big show in public to placate the hardliners in the Politburo, but who saved the world behind the scenes at the risk of his own life.