It can be easy to consider cyber warfare to be less serious than traditional warfare. But let’s be clear: cyber warfare is warfare. Information disruption and theft may not be physically obvious but experience shows that attacks on information, wherever they come from, have very serious consequences, both immediate and long-term. The world has less experience with cyber-physical warfare, but its effects are dramatic. Keep in mind that even small-scale damage to infrastructure can take months to fix, given the long replacement cycles for such equipment. You don’t run down to Home Depot and pick up a substation transformer. This type of equipment is built to order, with weeks or months of wait time, even in the best of circumstances. A large scale attack against physical infrastructure could overwhelm repair abilities and lead to huge delays restoring capability.