This raises the fundamental issue that businesses are becoming increasingly reliant on large scale IT infrastructure to run their businesses (Network Rail is going that way for running trains for example). When they go wrong you are totally helpless and the damage it does to the businesses and the inhuman nightmare it causes to people are incalculable. Some fundamental questions about this need to be address including is it all possible to "go manual" for some basic functions for example to at least let some planes fly. Otherwise, fingers crossed.