> And yet, you have not explained how reducing regulations is going to be done without also reducing safety.

I have.

The existing regulations prohibit safer alternatives. The safer alternatives are also less complicated and correspondingly less expensive. Using those alternatives would not only not reduce safety, it would improve safety, but they can only be used if those regulations are removed.

Here is an example. Older reactors require active cooling. If they lose electrical power for circulating pumps, they melt down. This is precisely what happened in Fukushima.

Alternative reactors use passive cooling. If you have no electricity, it doesn't matter, having electricity is not required by design. Which means you don't need a bunch of expensive multiply-redundant systems and contingencies to keep the power on.

But the new designs aren't allowed by old regulations, so things are more expensive and less safe than they could be.

> Regulations get added because new accident scenarios come to light, often due to near misses in existing plants. So one would expect a regulatory ratchet effect over time, even with perfect rational regulation.

That is what often happens, but it isn't what ought to happen.

There are two ways to address a near miss.

One is to make the minimal change to the existing design to address the issue, which is the only real option for already-existing installations. So e.g. reactors that require active cooling should have better generator redundancy. The other is to fundamentally change the design so that that category of problem inherently cannot happen.

The second one is what you want for new builds, but it's also what a low quality regulatory response expressly prohibits, or at best makes unnecessarily more costly. Because you end up with a rule that says "must have double redundant backup power generation" even for a design that doesn't require any power generation.

All you need instead of that is the ability for regulators to make timely and reasonable decisions. If there is a rule requiring backup power for pumps then it shouldn't apply to designs that don't need pumps, and if that isn't clear then the process for determining that and correcting the regulatory error should take two weeks rather than ten years.

> It's interesting to compare fission to another area of technology that has achieved high reliability in the face of accidents: commercial air travel. There, safety has been achieved on a pile of corpses.

That isn't really necessary. When you need a system to be reliable you build it with high tolerances and significant redundancy of safety-critical components. Then failures come in the form of "the expected maximum value for this variable was 100, the material spec supports values up to 400, but we measured a value of 150 in practice." Then the response is to replace the material with one that supports values up to 600. But there was never any danger, only a smaller safety margin than anticipated -- which is what the safety margin is for.

This is dramatically more difficult for aircraft than almost anything else because an aircraft requires active systems to prevent it from crashing violently into the ground. The normal failsafe of "emergency shutdown in event of serious issues" doesn't exist because you can't just shut down a plane while it's flying through the air at five hundred miles an hour and thirty thousand feet. So the requirement there isn't just "don't blow up" it's that you can't actually stop operating no matter what happens or everybody dies. Which is a much harder target to hit. And yet they still kill fewer people per mile than cars by two orders of magnitude -- while traveling ten times faster and with a hundred times more passengers per vehicle.

We know how to engineer things to be safe without making them uneconomical.