Fusion reactors could create ingredients for a nuclear weapon in weeks

Fusion reactors could allow a country to accelerate its development of nuclear weapons, producing the necessary radioactive ingredients in as little as a few weeks.

Nuclear weapons need specific radioactive isotopes, normally uranium-235 or plutonium-239, that can be easily split and start a chain reaction. This so-called fissile material is rare in nature, but can be produced artificially by a source that produces a lot of neutrons, such as a nuclear fission reactor of the kind in use today.…