Speculation like this is fun, but I think it&#x27;s little more than intellectual masturbation until we crack fusion energy. Until we understand the energy economy with such technology, and the most efficient way to leverage it, we&#x27;re not going to understand the most significant factors that we should be considering. And even then, we&#x27;ll only be starting to get the slightest clue of how Type II and III civilisations might work.