> There are no current nuclear designs that are naturally fail-safe;

That is fundamentally false. There are lots of designs and many tested reactors. Passive fail safety without any active effects are very much a common thing and mostly a standard feature in pretty much all modern designs.

Unless you have a different definition of 'active' then me. In the Molten Salt Reactor Experiment they literally hit the 'off' switch and went home for the weekend, shutting down the reactor was so basic. And the MSRE isn't the only reactor that has managed to do that.

There just not currently available commercially to buy of the rack.

If a nation seriously decided to invest in next generation nuclear, and were willing to put real money behind these designs, they could build them within a couple of years.

All the companies working on these designs have greatly limited, need to deal with very long wait times very limited facilities, need to overcome regulatory system not designed for those reactors.

If a nation picked a design, and really fast tracked development and deployment with all the needed work being done in parallel, a lot could be done.

To give you one example, the IMSR (Integrated Molten Salt Reactor) from Terrestrial Energy is in the very final stages of Phase 2 of pre-vendor design review. They are expected to finish Phase 2 within the next couple of months and that basically means the CNSC (Canada) has considered the design and there isn't any reason why appropriate construction license request wouldn't be approved.

> The objective of a review is to verify, at a high level, the acceptability of a nuclear power plant design with respect to Canadian nuclear regulatory requirements and expectations, as well as Canadian codes and standards. These reviews also identify fundamental barriers to licensing a new design in Canada and assures that a resolution path exists for any design issues identified in the review.

> A vendor who has completed a Phase 2 Pre-Licensing VDR, has committed to increased regulatory efficiencies at the time of licensing. The results of Phase 2 will be taken into account mainly for the Construction Licence Application and is likely to result in increased efficiencies of technical reviews.

https://nuclearsafety.gc.ca/eng/reactors/power-plants/pre-li...

So if a nation like Germany did a 180 and said, we need new reactor and we need them fast, but we only accept reactors that are passively safe, but all German industrial resources are used and this is a high priority project. They could probably build such a reactor in 3-4 years.

There are others one could talk about but I do like the IMSR.

> But more important is the implication that the reactor was known to be particularly vulnerable in comparison to all the other nuclear power stations in Japan, and the cost of fixing all issues of comparable a priori severity was within the capacity of the funding of the system.

Actually it was known that the sea wall was a particular weakness and it wasn't done, but not because of cost reasons. It was not done because it would have given anti-nuclear people a reason to say 'see it wasn't safe'.

So really like Shuttle issue, its a flawed safety culture that was the real reason. The required expense wasn't that high. And that matters just as much as cost issues.

However I generally agree. Saying 'it was preventable' isn't a good defense.