[pfdietz]

Solar and wind potential is enormous. The current world average primary energy demand is 18 TW, but the Earth is constantly being struck by 100,000 TW of sunlight. In no sense is a shortage of sun and wind an argument for fusion.

As for safety, the problem with fission isn't safety, it's cost. Trading off economics to obtain better safety is solving the wrong problem.

If fusion is not to be economical for 50 years, it will be competing against renewables (and storage) that have gone fully down their experience curves. In a world fully powered by PV, on the demonstrated historical experience curve, the LCOE from PV could be below $0.01/kWh (in today's dollars). Fusion will have a very difficult time competing against that.