Although allies of convenience during the Second World War, the Soviet Union and the United States entered into a period of tension from the end of the war until approximately 1991 when the Soviet Union dissolved.

The cold war can be characterized by nuclear weapons (Mutually Assured Destruction), Eastern Bloc (USSR) versus Western Bloc (North Atlantic Treaty Organization), indirect conflict (espionage, propaganda, embargos and even sports), and proxy wars.

Nuclear Weapons:  The war on Japan was concluded with the US dropping two nuclear bombs on Japan. The Soviet Union conducted its first successful nuclear test on 29 August 1949. The US raised the stakes with the first hydrogen bomb in 1 November 1952 which the Soviet Union matched on 22 November 1955. This period also saw a very large “Arms Race” between the two antagonists with other countries joining in such as the UK (1952), France (1960), China (1964), India (1974), Pakistan (1998) and North Korea ((2006). Israel is presumed to have nuclear capabilities but has not declared possession of such weapons. By the 1960’s both the US and the USSR had enough nuclear weapons to destroy each other not just once but several times over. Submarines gave both parties a “second strike” option where, even if attacked and wiped out, there was enough undersea ordnance to obliterate the other. This lead to a policy of Mutually Assured Destruction (MAD) whereby both sides understood that there was no first strike option to which the other side would not retaliate.

NATO and USSR: The cold war broke down geopolitically along the lines of control by the end of the Second World War. Countries that were either on the Allied side or held by the Allies at the end of the war joined the North Atlantic Treaty Organization (NATO). Similarly, countries that were a part of the USSR or held by the USSR; joined the Warsaw Pact.