Murphy's Law #3(Paraphrased): With any expensive & complex machine, it will be the 25 cent part that fails and brings everything to a screeching halt!!!
With society being as complicated as it is, it really doesn't/wouldn't take much to start that 72 hour clock to commenced the countdown to the stone age (for the 4th or 5th time around).
_________________________
QMC, USCG (Ret)
The best luck is what you make yourself!