That has a lot of collateral damage that may or may not be desirable though. Simultaneously it might have quite a different long term effect right? If all the actual computers are unharmed they can be powered in other ways in an emergency, even if at much higher cost. Or powered back up later, the time lost might be militarily very significant but they're not gone.

But how many people and companies actually have full functional decentralized clones of all programs and data? How many people and companies have devices that are locked to remote hosts they expect to check in on at least once in awhile even if they're not "cloud dependent"? What if all that was literally gone, a few thousand missiles or drones and data centers are all just completely erased including tape backups, everything, suddenly we're in a world where all that compute and data is poof. And without hurting anything else, no traditional war crimes either, no power or direct food or transport disruptions. Everyone is fine and healthy, except with this huge societal exocortex gone.