In a Cyber War Is It OK to Kill Enemy Hackers?

The new Tallinn Manual on the International Law Applicable to Cyber Warfare, which lays out 95 core rules on how to conduct a cyber war, may end up being one of the most dangerous books ever written. Reading through the Tallinn Manual, it’s possible to come to the conclusion that – under certain circumstances – nations have the right to use “kinetic force” (real-world weapons like bombs or armed drones) to strike back against enemy hackers. Of course, this doesn’t mean that a bunch of hackers in Shanghai are going to be taken out by a Predator Drone strike anytime soon – but it does mean that a nation abiding by international law conventions – such as the United States – would now have the legal cover to deal with enemy hackers in a considerably more muscular way that goes well beyond just jawboning a foreign government.

Welcome to the brave new world of cyber warfare.

The nearly 300-page Tallinn Manual, which was created by an independent group of twenty international law experts at the request of the NATO Cooperative Cyber Defense Center of Excellence, works through a number of different cyber war scenarios, being careful to base its legal logic on international conventions of war that already exist. As a result, there’s a clear distinction between civilians and military combatants and a lot of clever thinking about everything — from what constitutes a “Cyber Attack” (Rule #30) to what comprises a “Cyber Booby Trap” (Rule #44).

So what, exactly, would justify the killing of an enemy hacker by a sovereign state?

First, you’d have to determine if the cyber attack violated a state’s sovereignty. Most cyber attacks directed against the critical infrastructure or the command-and-control systems of another state would meet that standard. Then, you’d have to determine whether the cyber attack was of sufficient scope and intensity so as to constitute a “use of force” against that sovereign state. Shutting down the power grid for a few hours just for the lulz probably would not be a “use of force,” but if that attack happened to cause death, destruction, and mayhem, then it would presumably meet that threshold and would escalate the legal situation to one of “armed conflict.” In such cases, warns the Tallinn Manual, sovereign states should first attempt diplomacy and all other measures before engaging in a retaliatory cyber-strike of proportional scale and scope.

But here’s where it gets tricky – once we’re in an “armed conflict,” hackers could be re-classified as military targets rather than civilian targets, opening them up to military reprisals. They could then be targeted by whatever “kinetic force” we have available.

For now, enemy hackers in places like China can breathe easy. Most of what passes for a cyber attack today – “acts of cyber intelligence gathering and cyber theft” or “cyber operations that involve brief or periodic interruption of non-essential cyber services” would not fall into the “armed attack” category. Even cyber attacks on, say, a power grid, would have to have catastrophic consequences before it justifies a military lethal response. As Nick Kolakowski of Slashdot points out:

“In theory, that means a nation under cyber-attack that reaches a certain level—the “people are dying and infrastructure is destroyed” level—can retaliate with very real-world weapons, although the emphasis is still on using cyber-countermeasures to block the incoming attack.”

That actually opens up a big legal loophole, and that’s what makes the Tallinn Manual potentially so dangerous. Even the lead author of the Tallinn Manual (Michael Schmitt, chairman of the international law department at the U.S. Naval War College) admits that there’s actually very little in the manual that specifically references the word “hacker” (and a quick check of the manual’s glossary didn’t turn up a single entry for “hacker”).

Theoretically, a Stuxnet-like hacker attack on a nuclear reactor that spun out of control and resulted in a Fukushima-type scenario could immediately be classified as an act of war, putting the U.S. into “armed conflict.” Once we reach that point, anything is fair game. We’re already at the point where the U.S. Air Force is re-classifying some of its cyber tools as weapons and preparing its own rules of engagement for dealing with the growing cyber threat from China. It’s unclear which, if any, of these “cyber-weapons” would meet the Tallinn Manual’s definitional requirement of a cyber counter-attack.

The Tallinn Manual’s recommendations (i.e. the 95 rules) are not binding, but they will likely be considered by the Obama Administration as it orchestrates its responses against escalating hacker threats from China. Rational voices would seem to tell us that the “kinetic force” scenario could never occur, that a state like China would never let things escalate beyond a certain point, and that the U.S. would never begin targeting hackers around the world. Yet, the odds of a catastrophic cyber attack are no longer microscopically small. As a result, will the day ever come when sovereign states take out enemy hackers the same way the U.S. takes out foreign terrorists abroad, and then hide behind the rules of international law embodied within the Tallinn Manual?

image: No Face Hacker and Binary Code/ Shutterstock