Yes, Cyberattacks are perfectly Legal Under the Laws of War

What’s the fastest way to annoy someone who works in national security? Just say "cyberwarfare" and watch them combust. The term is meaningless in the worst way -- it puts the imagination into paranoid overdrive and is not limited by any legal definitions.

All the rules we’ve got on armed conflict today apply to ye olde bombs and bullets, not viruses and botnets. This makes a recent study from a group of NATO experts very, very welcome. Called the Tallinn Manual, it seeks to adapt the existing laws of war to cyberspace, laying down 95 new ideas over 282 pages. Many of them are just common-sense extensions of current international principles: According to one rule, cyberwarriors must take care not to hit the same targets that are off-limits to conventional forces. These include civilians, albeit with a crucial caveat: If you’re a civilian who’s decided to join the fight, you become a legitimate target even if you aren’t affiliated with a government or a military.