How the cold war begins?

Answer: The cold war began in June 1950. The first military action of this war began when the Soviet-backed North Korean People's Army invaded its pro-Western neighbor to the south. As a result, American officials feared this was the first step in a communist campaign to take over the world and deemed that nonintervention was not an option.

The term "cold" is used because there was no large-scale fighting directly between the two superpowers, but they each supported major regional conflicts known as proxy wars.