Why was the Cold War called 'cold'?

It was 'cold' because the two superpowers never fought each other directly. From the end of the Second World War until the Soviet Union dissolved in 1991, the United States and the USSR competed in almost every other way: an arms race, a space race, spying, propaganda, embargoes, even sport. The shooting happened elsewhere, in 'proxy wars' where each side backed opposite camps, so for many countries the Cold War was anything but cold.

The phrase itself has a literary history. George Orwell used 'cold war' in an essay published in October 1945, imagining a world under the shadow of the atomic bomb, with states that could not be conquered locked in a permanent 'cold war' with their neighbours. In April 1947 the American adviser Bernard Baruch applied it to the US–Soviet standoff: 'we are today in the midst of a cold war.' The journalist Walter Lippmann made it famous and traced it to a French phrase of the 1930s, la guerre froide.

Nuclear weapons kept it cold. Once both sides had the bomb, an all-out attack would have destroyed attacker and defender alike, a logic strategists called mutual assured destruction, or MAD. The scariest moment came in 1962, during the Cuban Missile Crisis, when messages between the two leaders took hours to arrive. Afterwards they set up a direct hotline. Despite the legend, it was never a red telephone: it was a teleprinter, and its first message was 'the quick brown fox jumped over the lazy dog's back'.