The Cold War was a war not fought directly but indirectly between the US and the USSR. The United States economy had boosted up during World War II and it was continuing to grow after and would continue for many years. There were enough jobs for almost all Americans and they were all living almost comfortably. When the Second World War was over the United States rose as the most powerful country in the world . They were also the only ones to have the atomic bomb. After a few years of being the only country with this power the Soviet Union created and tested an atomic bomb. After that moment it became a race of which country could create the most for protection and intimidation. As an American citizen this is when the Cold War started, with the successful test of the atomic bomb in USSR and uneasiness at its highest.
This was also the same time that communism and democracy began to bump heads. The US stood firmly on the side of democracy while the USSR stood for communism. The US believed that communism would eventually cause the same problems that Fascism did. The US wanted to contain communism to them. The threat of it spreading to other countries and eventually to the US became a fear for many Americans. It also brought about a fear that the enemy was not only overseas but perhaps a traitorous neighbor living right beside you.
The US had a goal of spreading democracy across the globe. With this goal they cut through the idea of the Russians wanting to end capitalism. The Soviets had been invaded a couple of times and wanted to set up a barrier to help protect them more. The Soviets and the US both felt like their way of life was in jeopardy and would do anything to prevail. The US and the Soviets wouldnt work together. If they had they would have a more successful chance of creating more for themselves. Instead they felt like they couldnt take the chance with letting the other break their trust.
Both countries did a good job in not letting the cold war become a nuclear one. President Truman decided not to use nuclear weapons in the Korean War. If he had the Soviet Union would have struck back with a nuclear strike on the US. President Eisenhower did not get involved in a revolution located in Europe. He knew the soviets wouldnt stand for it. The soviets also stood down during the missile crisis in Cuba. Many historians believed that both countries tried to keep altercations as low as possible. The Cold War had an enormous impact on the United States politically, socially, and economically. President Eisenhower also wanted to limit spending to save money for military defenses. President Kennedy helped spread hope to the young Americans.
No one really knows who started the cold war and has spread anger when being discussed. At first the soviets took all the blame for war. It made America look like it was just trying to do a good deed of spreading democracy. After many years it was looked at like maybe America had started it. It falls on the shoulders of President Truman for that. He made the Soviet Union out to be the greatest threat to the free world.  The war could have easily been triggered by anything. The route it took of course may have been prevented.
In summary, after World War II had ended the US had a super power weapon that could destroy nations. After the Soviets unlocked its secret the fear of them using them against the US was in the back of government officials heads. Along with the fact that the US was afraid that the Soviets communism would overtake their country didnt help the facts. The soviets were also afraid of the threat of a nuclear attack on them by the US. They also feared that America may spread democracy across Europe and possibly over take Russia.
 David Pierce, America in the Post War Period, Student Pulse, 1, no. 10 (2009): 1/1, http://www.studentpulse.com/articles/2/america-in-the-post-war-period (accessed January 18, 2013).  SparkNotes Editors. SparkNote on The Cold War (19451963). SparkNotes LLC. 2005. http://www.sparknotes.com/history/american/coldwar/ (accessed January 17, 2013)  SparkNotes Editors. SparkNote on The Cold War (19451963). SparkNotes LLC. 2005. http://www.sparknotes.com/history/american/coldwar/ (accessed January 17, 2013)
Pierce, David. America in the Post War Period. Student Pulse. 1. no. 10 (2009): 1/1. http://www.studentpulse.com/articles/2/america-in-the-post-war-period (accessed January 18, 2013). SparkNotes Editors. SparkNote on The Cold War (19451963). SparkNotes LLC. 2005. http://www.sparknotes.com/history/american/coldwar/ (accessed January 17, 2013).