Space reactors have extensive research. They would use a Stirling engine, not a turbine. Be about the size of a garbage can.

Right, but there's also a reasonable burden for those who pollute the most to do the most with the best tools. I remember looking at the stats for the top 20 coal polluting nations and only about 3 (Poland, Indonesia, Australia) don't already have nuclear energy. Australia outlawed it, but given their development index, small population, existing uranium mines, and vast coastline - they are the perfect mix of a would be nuclear success story. Both Poland and Indonesia are working on development of nuclear programs. If these nations built a supply chain and cooperative nuclear development consortium, we could knock out the worst of the coal burning in just a few decades. But we have yet to see anything close to a concerted effort like this, which makes me believe mother nature will inevitable "win" the climate change struggle.

Gotcha. Some would argue the contrary insofar as deployment time and ease. New nuclear has been taking some time, except in China.

Why would you describe it as energy inefficient? Heat conversion efficiency is just as good as any other thermal electric generator. With higher temperature reactors newer Brayton cycle could be used for 60%+ heat conversion efficiency. As far as mass to energy produced, there's nothing that even comes close, it's in a class all by itself with a 2 million to one mass/unit advantage over fossil fuels.

Conversely greater energy security and independence makes for a more stable economy and political climate.

Though power reactors don't make an easy path to bombs, more importantly the educational infrastructure a nation should mature to to support nuclear energy would provide the kind of brain power needed to get a weapons program started. Still never cheap or easy.

It's a valuable future resource. Absolutely no need to do this.

There's a lot of myths to unpack there. First, the USA is completing 2 new reactors in Georgia. As for accidents, the current fleet is run very well, and newer designs like the AP1000 design in Georgia are dramatically safer.

As for fusion being "the holy grail" not so much really for a few reasons: 1. Fission is so much easier to accomplish with the benefits of a clean waste stream, 2. As for efficiency, it depends on what aspect. For net energy return on energy investment, we shall see when the ITER project is completed in France, and conversion that depends on how much of that heat can be converted to electric energy. 3. The waste stream of fission is an easy to manage problem, especially relative to fossil fuels (zero management). 4. Gen 3 and 4 reactors take on the emergency cooling issues very well, and especially the scaling factor of the new reactors from Nuscale offer a repeatability to make a faster mass scale deployment.

So fission may not be perfect but fuels with far less energy density have made energy revolutions before (coal). Fusion just may end up needing a support network of fission reactors in order to make it cleaner from end to end, and if you're at that point then why add the extra layer of complexity with fusion? To me, fusion is a distraction from an already vastly superior fission reactors we can build now.