The problem with that is a loss of fusion over fission advantage. In addition to non involving high level waste or radioactive reactants (as long as D-T is down using Li6) and being an easily quenchable reaction, a fusion reactor would not use anything that could be turned into a nuclear weapon. Yes, fusion fuel is used in fusion bombs (actually that's tritium which would be directly used if Li6 was used), but these components are useless without a fission ignition source, which in itself is a powerful weapon.