Atomic weapon as an instrument of peace

Regarding the existence of nuclear weapons, which were never used all over atomic bombings of Nagasaki and Hiroshima as a tool of war against civilian or military targets during the Cold War, I try to give an explanation of "armed peace". I consider the question of why the two superpowers (the USA and the USSR) didn't start a "hot war" that would have been more likely nuclear. As an example of the most critical event will serve me Cuban Missile Crisis, with which can be the description of it understood in broader context. The paper points to the interrelations of opposing ideologies that related to atomic weapons have often drawn the same conclusions. I examine the military-strategic value of the atomic bombs which have shaped international relations troughtout the second half of the twentieth century. Besides the military aspects I also mention economic interpretation of the nuclear arms race and economic potential of the USSR and the USA. Why have in the first instance occured one-sided and than gradually overall disarment, reducing the number of nuclear warheads? I try to documented the explanation out of historical events also by using teoretical models.