In June 1950 the Cold War turns hot when American and British backed South Korea is invaded by the Russian and Chinese backed North. American technological superiority in both air and naval power lead to a blockade of North Korea but the land campaign becomes a stalemate. By 1953, with neither side any closer to victory and over 300,000 dead, fighting ceases. The Korean War demonstrates the importance of technology and innovation and by the mid 1950s, 40,000 defence contractors are working for the federal government. In 1959, America develops the first intercontinental ballistic missile. Capable of travelling 3,500 miles to deliver its payload, it makes redundant the need for a bomber to physically deliver and drop an atomic bomb. The heart of the Soviet Union, Moscow, is now the push of a button away.
In 1962, America finds out how vulnerable that makes a country feel when their U-2 spy planes show that neighbouring Cuba has nuclear warheads and delivery systems. The erection of the Berlin Wall by the Soviets the year before, effectively cutting the East off from the West, has dramatically raised tensions and literally drawn the battle lines between the two. The two superpowers have over 35,000 nuclear weapons, sufficient to wipe out all humans in the Northern hemisphere.
VIETNAM TO AFGHANISTAN
Russia backs down. This is the closest we've come to extinction. With the nuclear option unusable, the superpowers engage in the unwinnable wars of Vietnam and Afghanistan during the 70s and 80s. America and Russia, respectively draft and conscript hundreds of thousands of their own young men into wars against indigenous peoples presuming that an overwhelming technological superiority would be decisive. Both are defeated.
Ultimately, it's monetary, not military power, which wins the Cold War. During the 1980s, America's economy booms whereas Russia's continues to stagnate. It simply can't sustain the necessary arms race or its satellites states and in 1989, the Berlin Wall comes down.
By the end of the Cold War, rival countries have amassed enough fire power for over a million Hiroshimas. And the Americans have spent $5.5 trillion dollars on a war that never was.