At the moment I am watching a drama series on BBC TV in which (I think) state actors take complete control of the UK train network.
The scary thing is that many things could be hacked. Take for example power networks, oil and gas distribution, banking, air traffic control, sewage systems etc.. The threat to undersea cables is real, although thankfully there is a lot of redundancy meaning things are likely to be slower rather than totally non-functional.
I guess all cyber security services have to be mindful of threats and keep "ahead of the game". Also, any states contemplating such action knows they could suffer the same fate. A bit like the policy of "mutually assured destruction" with nuclear weapons, we hope these threats never come to pass.
In this day and age war could well be in the form of cyber warfare rather than conventional weapons.
