Terrorism is such a threat to modern cities partly because of the way we have organized our economies and transport systems as highly complex systems with few redundancies.
"Our financial systems, manufacturing industries, transportation networks, information systems and energy grids are, in some cases, extremely susceptible to attack. Some of these systems have critical 'chokepoints' -- like a key tunnel in a subway system or a high-voltage line in an electrical grid -- where flows of people materials or energy can be easily disrupted.
"Also, in our endless quest to maximize efficiency and to squeeze out the last bit of waste, we've reduced inventories, buffering capacity and slack within all our economic and technological systems. We've made them "tightly coupled" to use the jargon of systems analysts. At the same time, our demand for services from these systems has soared, as we've seen with our hunger for electricity. This combination of factors sharply boosts the risk of cascading breakdowns."
[Editor's note: Thanks to reader Luhrs Pollay for pointing out that this article is unfortunately only available to Globe and Mail subscribers, and not available with the site's free registration.]
Thanks to Michael Dudley
FULL STORY: Brittle cities are easily broken

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