Fusion promises to make this main problem worse, not better.
Fusion is a great example of solving the wrong problem.
Fission has two problems: the emotional one – weapons/danger, and the practical one – cost. Yes weapons could be a practical issue, but I think it's more an "emotional" issue.
The question is, is it only the practical reason that is preventing widespread adoption of fission power? On the surface, maybe! Unpacking it a bit, I'm not sure. Anti-nuclear sentiment has caused government policy changes, not the cost issue. Similarly, restricting nuclear power technology to only certain countries is a political issue, not a cost issue, and more closely aligned with the former.
Cost is a big issue, but I do wonder if we'd get over it if the danger aspect disappeared. The long term economics of nuclear power are actually really good, it's just that it takes ~10 years to realise those economics compared to (e.g.) ~3 for natural gas.
Nuclear's long term prospects are poor, for one big reason: it has never shown good experience effects. This means its cost has not come down with time. Any technology like that is doomed, if it has competitors that are improving. PV started off orders of magnitude more expensive than nuclear (levelized cost of energy) but now is much cheaper, because PV improved 20% for each doubling of cumulative production and nuclear didn't.
Good point, I hadn't considered this. I would suggest that a possible cause for this is lack of investment though. We had the 1st generation. Most current reactors are gen-2 or gen-3. Gen 4 hasn't really started use, still in R&D I think. There are ideas for Gen 5 but no progress. Each generation seems to bring moderate energy improvements, and significant cost, safety, and waste management improvements, but the interest just isn't there.
