> The Three Body Problem is great, but it assumes the existence of weapons of ludicrous destructive power.. The only other time I've ever seen a piece of fictio

> The Three Body Problem is great, but it assumes the existence of weapons of ludicrous destructive power.. The only other time I've ever seen a piece of fiction where someone had that amount of destructive power was in a cartoon. (And even then I only saw it once) That part doesn't seem to hard to me. A robotic spacecraft could install solar sales on a comet in such a way as to crash it into the target planet a few hundred years later. This could go unnoticed until it was too late by the target planet. Alternatively, a beam-powered probe (e.g. 'starwisp' or similar) moving at relativistic speeds could be crashed into the target planet. Neither of these require cartoon physics.