In the midst of escalating tensions between the U.S. and North Korea, Elon Musk, a pretty vocal critic of artificial intelligence (AI), has warned that AI poses a bigger threat to humanity than North Korea, and could start World War III.

Musk’s fear followed a statement from Vladimir Putin that, “Artificial intelligence is the future, not only for Russia but for all humankind. It comes with colossal opportunities, but also threats that are difficult to predict. Whoever becomes the leader in this sphere will become the ruler of the world.”

Musk added he was less concerned about the world leaders who want to start a nuclear war but “one of the AI’s, if it [AI] decides that a pre-emptive strike is most probable path to victory.”

The SpaceX founder doubts that North Korea can launch its own nuclear strike, saying “Pyongyang launching a nuclear missile would be suicide for their leadership, as South Korea, the U.S., and China would invade and end the regime immediately.”

Last month, Musk along with Deep Mind’s co-founder Mustafa Suleyman, and 116 experts on AI called the United Nations to ban the use of lethal autonomous weapons to prevent World War III. An open letter to the UN noted:

“Once developed, lethal autonomous weapons will permit armed conflict to be fought at a scale greater than ever, and at timescales faster than humans can comprehend. These can be weapons of terror, weapons that despots and terrorists use against innocent populations, and weapons hacked to behave in undesirable ways. We do not have long to act. Once this Pandora’s box is opened, it will be hard to close.”

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