Cost to extract power does not scale with power density of plasma. No optimistic projections for cost of extraction are better than idle speculation. Practical

Cost to extract power does not scale with power density of plasma. No optimistic projections for cost of extraction are better than idle speculation. Practicality of extracting diffuse 3H from a molten metal blanket, needed for fuel, is as previously noted purely speculative. Renewables are driving cost per kWh well below any plausible, or even aspirational, figures. The only fusion technology that has any chance of competitive extraction cost is Helion's, which does not depend on a round trip through heat. But it depends on a regular supply of 3He, a decay product of 3H which must be produced via operation, filtered from the working plasma, and then held for its 12y decay half life. It is anyway not clear if its process can be achieved at all. SMRs depend on the round trip through heat and incur all the other costs of traditional nukes, so offer no prospect of keeping up with plummeting cost of renewables. Fission's fuel rod meltdown is not the only catastrophic failure mode available. Fukushima demonstrated hydrogen detonation. Breached containment of thousand-ton inflammable, caustic, radioactive molten metal neutron absorption blanket would be adequately catastrophic.