Alec Ross is a senior fellow at Columbia University's School of International and Public Affairs. During the first Obama term, he served as senior adviser for Innovation to Secretary of State Hillary Clinton. Follow him on Twitter: @AlecJRoss
The playground fights I got into when I was a kid had closely observed, unwritten rules: you could punch, you could kick and you could even choke your opponent, but you couldn't use a weapon. Pick up a rock or a stick and bring that into the fight and you were going to earn the derision, and maybe a butt-kicking, from the entire playground crowd.
Similarly, during the Cold War there were some important, unspoken rules about combat. It was okay if militaries of Soviet and American satellite States fought and killed each other, but it was not okay for an American or Soviet soldier to engage one another directly, lest the uneasy equilibrium in that Great States conflict between the world's two superpowers be thrown off balance.
Today, utilizing cyber weapons falls into the category of largely being accepted (even if unhappily) as part of how countries exercise their power while falling short of the line of armed conflict treated as an act of war.
We will see if this can hold.
The latest example of firing off a cyber weapon is a Russian cyber weapon called Snake, also known as "Ouroboros" after a serpent drawn from Greek mythology. Ouroboros is wrecking havoc on Ukrainian government systems. It is interesting in that it has the characteristics of both a product of the intelligence services (the ability to surveil) but also of the military (the ability to physically destroy computer networks).
By targeting the Ukrainian government with Ouroboros, the Russians are able to effectively engage in an aggressive, kinetic act without actually declaring war or countries reacting like it is an act of war.
This will not last forever. If certain capabilities of Ouroboros go live then we will see if the playground rules hold. If the Russians deploy cyber weapons with network-destroying capabilities into other countries, there might well be one country that reacts as though the launch of a cyber weapon is no different than the launch of a missile. You see where it goes from here.
The absence of a set of broadly-held norms and treaties governing the use of cyber weapons has not led to the firing of guns or launching of missiles, but this will not always be the case. We need something more than playground rules.