Bulletin of the Atomic Scientists, Daniel Jassby: Fusion reactors have long been touted as the “perfect” energy source. Proponents claim that when useful commercial fusion reactors are developed, they would produce vast amounts of energy with little radioactive waste, forming little or no plutonium byproducts that could be used for nuclear weapons. But there is a hitch: While it is, relatively speaking, rather straightforward to split an atom to produce energy (which is what happens in fission), it is a “grand scientific challenge” to fuse two hydrogen nuclei together to create helium isotopes (as occurs in fusion).
