Answer :
The Korean War was already a proxy war during the Cold war: the Cold war has already been ongoing then.
The Berlin Blockade was earlier, and it can be assumed to be the beginning of the war: the Soviet Union decided that they can't risk loosing control of their occupational zone in Berlin
The Berlin Blockade was earlier, and it can be assumed to be the beginning of the war: the Soviet Union decided that they can't risk loosing control of their occupational zone in Berlin