Uranium deposits which are economically accessible for extraction and exploitation is much much much lesser than deuterium. Deuterium is ~0.02% of all hydrogen in water. Helium 3 contains not only on lunar surface but has around 37000 tons in Earth atmosphere. Is more than enough for hundreds or thousands years for humankind needs(if we use energy more effective and wisely).
The amount of Uranium "burned" in a nuclear reactor is almost completely negligible. 1
gram of Uranium produces 24MW-hrs of energy, equivalent to 3-
tons of coal. That's not even the most efficient reaction: Uranium-Plutonium cycles are even more efficient.
The USA has 47900 tons (47,900,000
kilograms) of economically extractable uranium. Australia has 1,692,700 tons (1-billion tons).
We're not running out of uranium. Its just not happening. And that's not even getting into Thorium reactors. The major issue with uranium is the high-cost of fission (safety concerns: not just vs natural disasters, but also terrorist threats), as well as the trust issue. Any country that purifies uranium is going to be immediately distrusted on the world stage... let alone a country that starts to stockpile Plutonium.
EDIT: This doesn't even take into account "Breeder Reactors", which generate more fuel than they consume.
https://en.wikipedia.org/wiki/Breeder_reactor. We have so much Uranium that we don't even bother building breeder reactors...
Thorium can't make a bomb. But that's also why Thorium is unpopular as a fissile material.
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Even nuclear bombs are highly efficient. A Uranium-bomb is just 10kg of purified Uranium (~1400kg of raw uranium) A Plutonium bomb is just 2kg (and Plutonium is easily made from purified Uranium roughly 1-to-1). We can sustain a nuclear war until the entire world is destroyed because of how efficient that damn material is.