In October, Facebook and its related social media platforms went down in mysterious circumstances for six hours. On the same day, China sent 52 military aircraft into Taiwan’s air defence zone, the largest and most provocative incursion yet. If military theorists are correct, headlines like these will be the precursor to World War III.

A Chinese invasion of Taiwan is a scenario that many fear will be the catalyst for the next major international war. And most pundits believe cyber warfare will play a major role in such a conflict, or indeed any future international wars. So a cyberattack that knocks out the American media to hide or distract attention from a Chinese move against Taiwan is not unrealistic.

To be clear, there’s no suggestion that the Facebook outage and the Chinese incursion were linked. But it’s a timely reminder of how vulnerable our networked world is to cyberattack. What role would cyberwarfare play in a future conflict, and is it as important as traditional ‘kinetic’ military operations?

There are three ways in which cyberwarfare may play a role: as an alternative to, as an opening gambit of, or alongside kinetic operations.

Some believe that the emerging theatre of cyberwarfare will completely displace traditional military operations, or indeed that it has already happened. That might be true, but if so it isn’t much to worry about. Shutting down Facebook, closing an oil pipeline or interfering with the operations of a power plant, airport, bank or factory are all disruptive and costly. But the damage is temporary, and the world moves on. Cybercrime is part of the background noise of a modern economy, whether instigated by lone hackers, organised crime groups or state actors. But that’s not to say it has no cost.

Defending against and dealing with cyberattacks are a drain on economic growth, but modern nation-states are robust and resilient institutions. If cyber operations are the sole plan a nation adopts to defeat an enemy, it would take a very long time and would certainly involve reciprocal action against the initiating side that might be similarly damaging. If that’s what World War III will be, we can rest relatively easy at night.

Of course, a highly effective cyberattack might shut down an entire country for some time. Imagine the disruption to a modern developed economy if it lost power, communications and access to the internet all at once and it continued for months. But such an attack would be so devastating that the victim would likely feel a line had been crossed and that it was an overt act of war. Retaliation probably wouldn’t be limited to cyberspace.

Cyber operations could facilitate kinetic operations (like an invasion of Taiwan, for example) by disrupting the other side’s communications so that its military hardware was temporarily powerless to respond. Modern military forces are blind without radar and satellite imagery, deaf without the internet and mute without secure telecommunications systems. In a short war, this might be all that’s needed. If Taiwan was temporarily blinded by a cyberattack, in a month the country might be overrun, without the Taiwanese getting off a shot.

But in a longer war, any benefit of throwing the first cyber punch will be temporary. Systems will inevitably be restored or workarounds found. A ship at sea can fire its guns and missiles without satellites. Tank crews and ground troops were perfectly capable of raining death on their foes before the internet. In World War II, Germany landed a devastating first blow on the Soviet Union in June 1941 when it launched a surprise attack—Operation Barbarossa—that caught the Soviet air force on the ground and their troops unprepared. Japan was also successful at knocking out large parts of the American Pacific Fleet at Pearl Harbor in a surprise raid. These initial successes didn’t bring the Axis victory. The greater resources of the Allies meant they recovered, wore down their enemies and crushed them. A cyber Pearl Harbor is no guarantee of enduring success.

In a long, drawn-out modern war, cyber operations will play a part. Military forces may no longer be able to rely on the satellites they have grown so dependent on. Expensive weapons platforms that rely on modern communications to operate may prove a wasted investment compared to old-fashioned tanks, guns and artillery.

But cyber operations are unlikely to be decisive on their own. For years, airpower enthusiasts were predicting that strategic bombing would replace the need for traditional ground operations. We’re still waiting. Airpower alone has never won a war (as distinct from contributing to victory). Events are normally decided on the ground. In the same way, future wars are unlikely to be decided in cyberspace alone.

The real danger of cyberwarfare is not that it will replace kinetic operations, but that it will incite them. The line between war and peace is reasonably clear when dealing with tanks, warships and aircraft, but it is grey when dealing with malware and online bots. If countries feel safer engaging in conflict behind the veil of anonymity provided by the internet, the risk of a catastrophic miscalculation increases.