According to recent research, the Internet is vulnerable in precisely the sort of way its design was meant to avoid--paralysis of the entire system through the destruction of particular nodes--and the commercialization of the Internet is partly to blame.
Three scientists have concluded that if key nodes of the Internet were compromised by an electronic attack or a physical disaster, major cities w/ redundant nodes would most likely survive the increased congestion that would result from rerouted traffic, but outlying areas would suffer and perhaps lose connectivity altogether.
The researchers suggest that the commercialization of the Internet has concentrated distribution points and effectively made the Internet as a whole more vulnerable to such localized attacks.
In its early days the net was as decentralised, as possible [sic] with multiple links between many of the nodes forming it. If one node disappeared, traffic could easily flow to other links and route traffic to all parts.
However, said the researchers, the increasing commercialisation of the net has seen the emergence of large hubs that act as key distribution points for some parts of the web.
As a result, the net has become much more vulnerable to attack.
Report is here.