The notion that vital infrastructure is highly vulnerable to attack is not something which is new or even really that related to this particular incident. The d

The notion that vital infrastructure is highly vulnerable to attack is not something which is new or even really that related to this particular incident. The damage caused by this incident was relatively limited, mostly to a cable vault, which will require a lengthy and expensive repair but is far less destructive than it potentially could be. A much more interesting incident to look at is the Metcalf attack, which is both more mysterious in terms of the perpetrators and more clearly intended as an attack on vital infrastructure. As a proof of concept, Idaho National Laboratories conducted a somewhat infamous experiment in which they demonstrated it was possible to cause significant permanent damage to a common diesel standby generator via network intrusion. Multiple levels of the federal government and private industry (including industry bodies in electrical and telecom) recognize vital infrastructure as a significant vulnerability. However, very little attention has been paid to the issue. Part of this owes to it being fairly bureaucratic and uninteresting in the details, part of it is because progress is very slow due to the scale of the problem and cost of making significant changes. In the telecom industry, for decades now telephony has moved towards protocols with significantly more flexible routing and recovery options, improving the reliability of long-distance telephone calls to such a degree that you virtually never encounter a failure. Unfortunately, redundant connectivity to individual customer sites remains something which is expensive and so fairly uncommon for even larger businesses. Legacy issues in the design of the 911 system and infrastructure to PSAPs has also repeatedly lead to 911 outages in response to relatively minor issues (single points of failure are very common due to the architecture of the system). So, local service disruptions are easy to achieve by means like this. Nationwide ones are fairly difficult, at least without careful planning and some luck. This is all to say that the concern is very real, but this particular incident doesn't seem like a top example of it. In fact, one wonders why, given the high degree of vulnerability of many infrastructure sites, terrorist attacks on infrastructure are less common. I would guess it's because causing infrastructure disruption which leads to fatalities requires a fairly complex, concerted effort, which could probably still lead to more fatalities if directed at a more conventional form of attack. All in all, it's a return on investment consideration for terrorists.