How Close the Human Race Came to Ending Life on Earth Every Year Since 1947

Two years after the end of World War II, world nations are aligning themselves either with the East, the Soviet Union and communism, or with the West, as the world is gearing up to the Cold War. The clock makes its debut at seven minutes to midnight.

The Soviet Union attempts to take control of Berlin by blocking all road traffic to the city, fueling tensions between the communist country and Western powers.

The Soviet Union tests its first nuclear weapon. The Bulletin states, “We do not advise Americans that doomsday is near and that they can expect atomic bombs to start falling on their heads a month or year from now, but we think they have reason to be deeply alarmed and to be prepared for grave decisions.” The clock is advanced from seven to three minutes to midnight.

The conflict between North Korea, which is supported by communist China and the Soviets, and South Korea, which is supported by the U.S., breaks into war in June. Often called the forgotten war, the Korean War would end in 1953.

The nuclear threat continues to hover around the world in 1951. Julius and Ethel Rosenberg are convicted of passing U.S. nuclear secrets to the Soviet Union and are sentenced to death. Yet for the first time electricity is generated from a nuclear power plant.

Britain joins the nuclear club when it tests its first atomic weapon.

After the Soviet Union detonates a thermonuclear device, then Secretary of State John Foster Dulles tells the United Nations that “physical scientists have now found means which, if they are developed, can wipe life off the surface of the planet.” Meanwhile, the U.S. decides to pursue a hydrogen bomb, a more powerful explosive than an atomic bomb. The clock advances from three to two minutes to midnight.

The U.S. launches its first nuclear-powered submarine, the USS Nautilus. Secretary of State John Foster Dulles tells the Council of Foreign Relations the U.S. will protect its allies with “massive retaliatory power,” in what is believed to be the first statement in the doctrine of “mutually assured destruction.”

To push back against the growing influence of NATO, which was founded in 1949, the Soviet Union and several Eastern European countries formally sign the Warsaw Pact. Countries include Albania, Poland, Czechoslovakia, Hungary, Bulgaria, Romania, and the German Democratic Republic (East Germany).

Although it signed on to the Warsaw Pact, Hungary bristles under Soviet rule. A rebellion is quickly quelled by the Soviets.