The interconnection/cascade failure theory is nothing new. Roberto Vacca is considered the originator of the concept in the 1970's, when he wrote about it in his non-fiction work titled "The Coming Dark Age". He noted that if you're no longer getting mail delivery on a regular basis, then that's a pretty good indication that the government is no longer functioning. Of course, the first world has become totally dependent upon complex interconnected technology. The interruption of the internet wouldn't faze a Bedouin tribesmen, but the same outage could cause a catastrophic disaster in New York City.
With the just-in-time delivery/inventory systems being used today, any small interruption in communications or transportation could cause a major shortage of critically needed foodstuffs. We live in interesting times.
In a report I wrote for FDNY I listed one of my warning signs that a low-yield nuclear weapon had been detonated in NYC was that cable TV service would be interrupted.