If I recall correctly, there is a way to recombine nuclear waste into useable nuclear fuel. This new fuel is useable in nukes, which is why we store all of our nuclear waste now instead of recycling it. So: even if we were to run out of plutonium for nukes, we could simply recover the waste and recycle it into new nukes. That said, I think it would be a whole lot better to use said fuel to generate energy than to delete humans.
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If I recall correctly, there is a way to recombine nuclear waste into useable nuclear fuel. This new fuel is useable in nukes, which is why we store all of our nuclear waste now instead of recycling it. So: even if we were to run out of plutonium for nukes, we could simply recover the waste and recycle it into new nukes. That said, I think it would be a whole lot better to use said fuel to generate energy than to delete humans.
Geological processes also create oil, but your point about running out of fusionables is still valid.