I've never heard of "non discretionary side of the economy". What is that? Do you mean only use money when necessary? By eliminate debt and conserve I assume you mean personally since you were answering a question.

A huge interconnected beast can be very stable and robust, if the connections support each other. One of the buzz phrases I learned in an ecosystems course was "diversity breeds stability" meaning that an ecosystem with many ecological niches can remain stable and productive in the face of an disruption. If something happens to a part of the system it tends to heal itself. Maybe our ecosystem just needs a few years to adjust to some of the energy production being siphoned from nutritional needs to transportational needs.

Just in time systems work when the everything in the supply chain is predictable, the inventory should be some measure of uncertainty in the supply chain. So if uncertainty increases more quickly than inventory space can be created and filled, you get problems. I think what you're worried about is that businesses quickly dumped warehouse space when their supply chains became more reliable through information technology. But they can't build warehouses as quickly as they dumped them so if the supply chain suddenly becomew unreliable for whatever reason they'll have problems until they can recover the reliablilty or inventory space.