Many things, not just one. 1971 Nixon Shock https://en.wikipedia.org/wiki/Nixon_shock 2010 Dodd-Frank https://www.investopedia.com/articles/markets-economy/090… 2012-2013 Cypress https://en.wikipedia.org/wiki/2012–2013_Cypriot_financial… 2018 BIS https://www.bis.org/speeches/sp180323.htm