I've seen a number of comments, both at TheOilDrum and elsewhere, suggesting that the US is now less susceptible to supply disruptions because we have reduced our demand for oil by several hundred thousand barrels per day over the past year. In general, I get the sense that people think we can insulate ourselves from supply disruptions, from our dependence on potentially unreliable foreign sources of oil, by improving our efficiency and eliminating "unnecessary" oil consumption. In my opinion, this is backward. In this post, I will argue that, because the demand that is destroyed first in a free market is the demand that is easiest to eliminate, the resulting consumptive system is more inelastic, more brittle, and more susceptible to systemic shock from supply disruption. I will approach this argument by outlining what makes a system either resilient or brittle and why market-driven demand destruction creates a more brittle system. I will conclude with a few thoughts on how we can increase the resiliency of our energy-driven economy in a future environment of declining energy supplies.