Who is most to blame for the Cold War?

After the surrender of Nazi Germany, the relationship of Allies started undermining when Truman and Stalin disagreed over several issues such as how to divide Germany and the size of reparation. Through the next five years, the allies became instead enemies and the Soviet Union is to be partially responsible for this. Germany was always one of the biggest disagreements among the Allies. As mentioned, Truman and Stalin failed to agree on the size of …

…each other's action, which grew bigger and bigger. By 1949, the tension grew non-stop, NATO, FDR and GDR were created, and nuclear bomb race began when USSR invented its own atomic bomb in 1949. Later, Warsaw Pact was created in respond to the NATO, Korean War, Hungarian Uprising, Cuban missile crisis etc. From this, we can see it's a pattern by both sides; it is developed one by one but not wholly by someone at a time.