Could gene editing tools such as CRISPR be used as a biological weapon?

The gene editing technique CRISPR has been in the limelight after scientists reported they had used it to safely remove disease in human embryos for the first time. Concerns are mounting that gene editing could be used in the development of biological weapons. In 2016, Bill Gates remarked that “the next epidemic could originate on the computer screen of a terrorist intent on using genetic engineering to create a synthetic version of the smallpox virus”.