Final answer:
During the Bipolar Cold War from 1947 to 1989, the two major centers of power were the United States and the Soviet Union, representing capitalist and communist ideologies respectively.
Step-by-step explanation:
In the Bipolar Cold War international system that spanned from 1947 to 1989, the two major centers of power were the United States and the Soviet Union. These superpowers represented opposite ends of the ideological spectrum, with the U.S. advocating for capitalist democracy and the USSR for communist authoritarianism.
The era was characterized by the Cold War, during which these nations exerted their influence globally, creating spheres of influence that avoided direct military conflict but engaged in proxy wars, technological competition, and an arms race, known as Mutually Assured Destruction (M.A.D.). This bipolar structure led to a divided world, where countries largely aligned with either the capitalist block led by the U.S. or the communist block led by the USSR.