At the end of WW II, the Soviet Union had spread throughout Eastern Europe and had half of Germany, creating a series of satilite nations all governed by Soviet friendly political systems, based on Soviet style communism, ( excepting Yugoslavia - Broz Tito refused to submit to Russian influence).. Part of the reason from the Russian perspective had to do with feeling the need to create a buffer between Russia and the Western European non or anti commumist countries.. Remember Russia lost 22 million of her citizens in WW II from NAZI German aggression. . . From the end of WW II and on through the decades of the 50, 60s , 70s, on up to 1991... The US and US aligned. nations kept up a military defence using both strategic nuclear and tactical conventional forces stationed around the globe positoined to neutralize or counter Soviet military capability. . And there were scores of proxy wars where the US and Russia provided weapons and advisors to the governments of foreign countries that fought each other. . . You will want to do some reasearch on this. . It was called the cold war because beyond Korea, where we fought Chinese forces in 1951, we never actually went to war with Russia. Went on for 50 years.