[fusionadvocate]

That is incorrect. Recent advances using attosecond lasers enable new tricks and fusion conditions to be realized tabletop. Search also for plasmonics. Using nano antennas and intense lasers to accelerate protons and electrons in a tabletop device (previously required large machines).

[ben_w]

Fusors already enabled desktop fusion reactors, literally high school science fair projects even a couple of decades back.

What stops Fusors and Polywells from having already given us this decades ago with P-B11 etc. is that the cross section for fusing is so much lower than the cross section for elastic scattering, and that elastic scattering loses so much energy to EM via bremsstrahlung.