A little while ago, I was alarmed to hear a former security official warn of the dangers of a cyber 9/11. The fear was that terrorist hackers could unleash mayhem by crashing critical infrastructure such as electricity grids, financial networks and air traffic control.

I was relieved to hear another security official later argue that this was a bad historical comparison. But his own analogy was even more unnerving: August 1914. Such was the opacity of cyber space that the risks of massive miscalculation resulting in catastrophic escalation were hair-raisingly high. The ultimate nightmare was that we might sleepwalk into a cyber-Armageddon, just as Europe’s political leaders had stumbled into the first world war.

It is easy to paint scary scenarios. Our world is becoming ever more dependent on electronic, rather than physical, links. The chip designer Arm Holdings estimates that some 1tn connected devices may be in use by 2035. There are massive benefits to such interconnectivity. But there are enormous vulnerabilities in such hypercomplexity, too. Almost every device is a potential point of weakness and a gateway to a bigger networked world.