I'm highly skeptical, for three reasons: 1) He3 fusion requres much higher temperatures than other kinds of fusion, so it's even farther away from our grasp th

I'm highly skeptical, for three reasons: 1) He3 fusion requres much higher temperatures than other kinds of fusion, so it's even farther away from our grasp than ordinary fusion. This makes the "low-radiation" aspects of He3 irrelevant. 2) There isn't that short supply of He3 on earth, in particular there is quite a bit in natural gas, something like 30 kg produced annually just in the US at current rates. 3) You need a huge installation on the moon processing millions of tons of regolith. Basically large scale strip mining on the moon. Big, energy demanding mechanical equipment that requires frequent maintenance and spare parts and human intervention (just ask any regular miner) while being subjected to extreme temperature swings doesn't sound like something I'd want to put in space. And we haven't even mentioned the environmentalists and the relevant space treaties yet.