When the idea of re-creating the process that powers the sun here on Earth felt more like a thought experiment or a science fiction premise than a viable part of our global energy mix, it was easy to imagine equally far-fetched outcomes. We imagined that fusion would be limitless, unstoppable, the holy grail of clean energy and a silver bullet for the climate crisis. But now that commercial nuclear fusion is finally growing closer to reality, it’s time to ask questions about the actual logistics of scaling the technology up and out, and to…