“even though thorium isn’t itself a fissile material.”
Editor did not fact check this!
If it’s not fissionable, then what fissions inside the reactor?
Or does he mean bomb-type fissionable? Th 233, odd Z, half-integral spin, low spontaneous fission rate, hmmm....
IIRC, under neutron bombardment, Th233 becomes U233, which is fissile
thus the need for a breeder reactor