What will Fusion give us that Fission can't already? Is it safer perhaps?
Realistically, today, it's only better because of decades of lobbying and propaganda for fear mongering around fission. There is no reason why nuclear energy couldn't be the vast majority producer of all electricity in the world while massively lowering environmental damage and loss of human life.
Long term, fusion might be better because it can produce a lot more energy and be safer. I feel like the safety improvement is negligible however compared to modern fission reactors that are properly maintained and governed.
Since you brought up lobbying, it's fascinating to me how many nuclear power fans the industry has created who are not informed by data and facts but are utterly convinced that nuclear power is the solution to all our energy issues.
Certainly, fusion does have the big advantage that it makes far fewer Curies of radioactive material per kWh as it operates. That has been the main driver of nuclear fission safety and waste issues.
On the other hand, there are good arguments suggesting that conventional fission has been reasonably good at containing and controlling the radiation, such that it's among the safest and cleanest forms of energy known already. But the PR issue is a hard one, and people don't think like actuaries.
That being said, fission is already pretty darn safe. But the public perception of it is not good.
> Surely Fission provides us with unlimited carbon free energy (given enough fissionable material).
The crux of the problem is, there is a limited supply of fissionable material. If we manage to survive as a species, our energy demand will continue to grow, and one day we would meet a hard cap, limiting what humanity as a species, is able to do.
As a very very rough estimate, if we burnt through all the fissionable material that we have available on earth, it would be about enough energy to launch the mass of Mt. Everest into orbit. Long term (as in, many generations from now) we will need more energy than that.
