SpaceX head Elon Musk and other industry leaders write that autonomy will lead to wider and faster war.

The prospect of tanks, machine guns, and drones that think for themselves becoming widespread is giving tech luminaries the heebie-jeebies.

In an open letter today (Aug. 21), a group of specialists from 26 nations called for the United Nations to ban the development and use of autonomous weapons. The signatories include Tesla CEO Elon Musk and DeepMind co-founder Mustafa Suleyman, as well as other leaders in robotics and artificial-intelligence companies. (Google acquired DeepMind in 2014.)