[thfuran]

>hypothetically if nuclear fusion is solved, wouldn't that be the one of these three with the largest incentive to fix overnight?

Maybe but it's the only one that'd take probably several trillion dollars in infrastructure spending on top of just knowing how to do it. There's a huge difference between "net positive energy fusion reactor" and "economically viable fusion energy generation" and another huge gap between that and "fusion reactors are the primary means of energy generation". The other items are achieved either by a proof or by proof of concept / trial.