But that said, your assertion, your burden of proof. Convince me.
But that is just my point. There is no empirical reason to believe or disbelieve in 2B2F. There are myriad political reasons to do both. Not all questions must be answered, and if this is the only sort of answer available, I'll pass.
The loss of Lehmann in 2008 very nearly precipitated this, and in multiple histories of the 2007-2008 crisis, it's cited as the reason that a bailout was created.
The most notable instance in the past century was of course the Great Depression precipitated by the Great Crash of 1929. If you've not read John Kenneth Galbraith's book on the topic (short, comprehensive, and highly readable), I very strongly recommend it. It was precisely a case of general financial contagion brought about by grossly excessive moral hazard, and spread throughout the world.
There's a long list of financial panics caused by the failures of single firms, generally financial or with a significant financial impact:
https://en.wikipedia.org/wiki/List_of_stock_market_crashes_a...
In the sense of creating regional depressions or declines in economic vitality, there's a long history of manufacturing first entering, then departing, various locales. This happened in many of the former factory towns of England, then New England, the Steel Belt extending from Pennsylvania through Ohio and Michigan in the U.S., the garment and furniture industries in the southeastern U.S., and the aerospace and defence industries in Southern California following the 1990s defence budget cuts. Or pretty much any extractive industry boomtown anywhere.
Some of those have left lingering poverty, others simply resulted in a former golden age which has never fully recovered.
