I like the idea of siting them underground, which completely addresses the aircraft strike vulnerability. Physical security is also easy when they're undergroun

I like the idea of siting them underground, which completely addresses the aircraft strike vulnerability. Physical security is also easy when they're underground. Thorcon was pursuing this, but has switched to a ship-based approach. Searching today, I found a new (to me at least) company that's working on a truly small reactor, 3-15 MW electricity, and is planning on underground siting: https://www.usnc.com/mmr/ https://www.usnc.com/mmr/ It also supplies 10-45 MW of thermal, so great for poleward climes. Fission will be a critical technology going forward, until fusion generation can compete on power to size/weight ratio...and cost. And until aneutronic fusion power is practical, there's no large benefit to fusion regarding waste.