Re: Thorium Cycle Reactors
Thorium reactors have been built, but not for some time.
Why? Because they don't produce tasty isotopes of elements like Plutonium, so the military/government gains no benefits, doesn't put in any investment--. Look at where all the fundamental money for Uranium fission technology came from.
Add to that the reduced need for complex mining operations, and the near-elimination of all those juicy waste reprocessing, storage and decommissioning contracts, and it's no wonder the commercial nuclear operators aren't interested. No gravy train.
I understand, though, that India and China are putting money into Thorium.