I think the lack of requirement for enrichment is quite the tradeoff for a lower fuel efficiency, especially considering that not only is uranium quite plentiful on Earth, but Canada is the top three producer of the stuff as well.

That said, I might be wrong on some of the details I mentioned, as I’m working from memory and I’m not nuclear physicist, but I’m sure that the physics for a fast neutron reactor is pretty different from high pressure reactors the US uses.

I haven’t heard that the US had ever rescinded the law on recycling nuclear fuel, though I have heard about how much cheaper it is to mine and refine more than to recycle used fuel. Those are the sort of stuff that market regulations will never address, and is why government regulation and intervention is so crucial.

And I also do understand that the amount of high level waste in the US isn’t really a significant amount anyways. Most numbers that people throw around include low level waste, and I think they’re only marginally dangerous for a year or less? It’s all burned or thrown in regular dumps after about that long as things stand anyways.