Sure, it could happen. There were hospitals that got knocked out for weeks with as simple ransomware attack.

If you have a dedicated hacker with means to acquire exploits, security is probably almost impossible. This is why effective mitigation is very likely the safer approach. Manual overrides or air gapped systems would help too.

But it is wrong to panic about it. The best mitigation is boring, but yes, some investment in IT could really help.

Got a link to a news article about such an event?

> A government-sponsored test

So not an actual event.

An actual event would be an act of war. Base assumption is that most systems are currently compromised and on standby.

Maybe you missed Stuxnet / Olympic Games? Not sure how much ICS/SCADA security work you do, but there's a whole field dedicated to it. Can't tell if this is just someones narrative shaping work or sincere ignorance.

Anyone who has gone to a recent security conference and walked away feeling secure wasn't paying attention.