The 45 year Cold War was a period of dramatic change and increased prosperity. The tensions at the end of WWII to a large extent were forgotten by the 1990’s. I examined the ideologies and foreign policies, arms’ race and the Cuban Missile crisis, political personalities and economic power. The influence of these varied over the Cold War period with these different factors both escalating and de-escalating tension at different times. Underlying this is the economic power of the United States and the Soviet Union and the fact that wars even Cold Wars, cost money and this I believe was a key factor in initially escalating the war through the arms’ race and de-escalating as the Soviet Union collapsed.
There are a number of factors which resulted in the de-escalation of the Cold War. Many of these are combined in the section above. These include differences in ideologies, especially immediately after World War Two which seemed to become of lesser importance as the Cold War progressed. There were also economic factors, including the collapse of the Soviet Union, and the resources needed to sustain the arms race and ensuring that nuclear weapons were ready to be launched as a counter-attack. The concept of Mutually Assured Destruction (MAD) got to a point where both superpowers had the capacity to destroy the other. It then became more of a neutral factor. Politicians and their personalities also had an impact on the outcome of the Cold War some escalating the conflict such as Truman and Reagan and others such as Kennedy and Khrushchev de-escalating. Time and changes in foreign policy also influenced how the countries reacted to events in the Cold War.
This is simplistic and does not recognize the spread of communism and capitalism beyond the superpowers with capitalism appears to hold sway.