How far did Cold War tensions increase in the 1950s?
The USA set up a network of anti-communist alliances around the world that included NATO, SEATO and CENTO. This increased tensions with the USSR because they saw the alliances as aggressive and trying to encircle the communist world.
The USA and USSR engaged in an arms race in which they both developed bigger, more deadly and technologically advanced weapons, such as short range and intercontinental nuclear missiles. This increased tensions because both countries realised they were the weapons of the future as the bombs killed thousands of people instantly.
What impact did the arms race have on the world?
The US began spending more money on nuclear missiles in the 1950s and 60s because it was believed there was a missile gap (that the USSR had more missiles than them). Therefore, successive presidents began spending more money on nuclear missiles to show that they were trying to reduce this 'missile gap'.
The MAD (Mutually Assured Destruction theory) may nuclear war less likely because the USSR and USA both believed they had huge numbers of nuclear weapons. They both feared that if they launched a nuclear attack, the other superpower would retaliate. Therefore, the fear of the mass destruction that a nuclear war would bring served as a deterrent for war.