Sadly, unless our future energy requirements have been vastly underestimated, economics is also going to make commercial-grade fusion unattainable. Like fission, it's development ultimately requires the vast sums only wealthy nations can provide. But even once fusion is achieved beyond breaking even, only those same wealthy nations will be able to pay, more likely massively subsidize, before any fusion power plant could dream about existing.

This is why I think society should abandon centralizing power generation and require all structures to generate they're own green power. While massively less efficient than centralized power generation and distribution, with clean energy generation like solar & wind, and necessary optimizations such as more efficient climate control, we can afford to be less efficient.