Where Amir Sufi and Atif Mian go wrong in their explanation of the different economic consequences of the dot-com bubble and the housing bubble,
In general, economics treats money as an "illusion" in that it facilitates the trade and exchange of real goods and services, but fundamentally does not impact or distort that exchange (at least to no great degree). A rose is a rose is a rose, and therefore a good is a good is a good regardless of whether it's prices in dollars or shekels. Therefore, money in general and banks in particular do not play a central role in macro monetary models, which instead focus on things like time preference, consumer expectations, etc.
In reality, money, or more particularly credit, plays a central role in the economy because of how bank lending works. When banks lend, they lever up their balance sheet, and therefore create money out of "thin air", constrained only by capital requirements on the supply side, and the number of qualified borrowers on the demand side.…
These two $6T are not comparable. In the dot-com bubble, the loss wiped out venture accounts and household wealth in brokerage accounts, but neither was enabling additional lending (and therefore money supply). In the housing bust, $6T of bank capital (which collateralized the loans) was propping up an additional $120T or so (at a 5% capital requirements ratio) of money supply, so the impact on the economy was over an order of magnitude greater.…
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The Housing Bubble involved banks
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