Why the cold war because it did not actually lead to real direct fighting, or hot war, between two sides, on a wide scale. Period from 1945 (the end of wwii) to 1991 (the breakup of the. Who against who western bloc vs. eastern bloc [or nato vs. warsaw. Why cold war ideological difference and national interests conflict. Here are some important information to understand the origins of the cold. The allies delayed to open a second front in europe: postwar territorial divisions. Asia (japan and korea): two visions of the postwar world. Us hoped to shape the postwar world by opening up the world"s markets to capitalist trade, bring peace and democracy to the world; Ussr wanted to secure its vulnerable frontiers [it had been repeatedly invaded by western powers] and develop socialist movement; The dispute over germany [rebuild or destroy]: the truman doctrine and the marshall plan. The truman doctrine: a policy of containment [no communism beyond.