The biggest problem with nuclear power generation is external to the technology, it depends on the legal and regulatory regime, and how good a safety culture the country can develop for it.

On the latter factor, Japan has amply demonstrated over 3+ decades they have absolutely no business doing anything in this area (a judgement I reached long before Fukushima). To compare to a vaguely comparable culture, the PRC seems to be doing well, but wonder if that's due to a much greater lack of transparency.

While I haven't looked at it closely, France sure seems to be doing well (76% of their electricity production, at good points and with lots of exports), but the usual political suspects propose to fix that. Canada as well??

The US finished going bat-shit crazy on the subject under Carter (perhaps because he was on the cleanup crew of this first generation (1947) reactor after it suffered a meltdown: https://en.wikipedia.org/wiki/NRX, and, yeah, it's another reactor with a positive void coefficient). You're not going to see economic nuclear power in the US for the foreseeable future unless you foresee a counter-revolution that removes power from the NIMBYs and BANANAs.