I see, but still, at least the energy source itself would be proven technology in the form of H-bombs right? As for the shielding, do you mean the pusher plate

I see, but still, at least the energy source itself would be proven technology in the form of H-bombs right? As for the shielding, do you mean the pusher plate or the nuclear shape charge in the bombs themselves? Does going from fission to fission+fusion bomb make such a big difference that couldn’t be overcome just with more/stronger material and/or ablative shields?