During the Cold War, the term "Kremlinology" referred to efforts to understand what was taking place at the commanding heights of the Soviet Union — indeed, behind the entire Iron Curtain.
Kremlinologists monitored (in whatever way possible) who was up and who was down among the core Soviet leadership. Great significance was read into who signed an official document, or who stood where atop Lenin's Tomb in Red Square when reviewing military parades.
All of that was grammar-school stuff compared to efforts to decipher the regime in North Korea, where the truth is far more opaque.