NancyLebovitz:

The economic crisis of 2007 was another viewquake for me. I literally went around for a couple of months muttering about how I had no idea it (the economy) was so fragile. A real estate bust was predictable, but I had no idea a real estate bust could take so much with it.

That depends on what exactly you mean by "the economy" being fragile. Most of it is actually extremely resilient to all sorts of disasters and destructive policies; if it weren't so, the modern civilization would have collapsed long ago. However, one critically unstable part is the present financial system, which is indeed an awful house of cards inherently prone to catastrophic collapses. Shocks such as the bursting of the housing bubble get their destructive potential exactly because their effect is amplified by the inherent instabilities of the financial system.

Moldbug's article "Maturity Transformation Considered Harmful" is probably the best explanation of the root causes of this problem that I've seen.