BOOM BURST BOOM

Things were looking frothy when we warned of “the great cryptocurrency bubble of 2017.” The combined market capitalization of cryptocurrencies had ballooned 870%

to more than $100 billion in just 12 months—more than six times the stock market’s rise during the height of the 1990s dotcom bubble. “Buckle up for more blowups, more Mt. Gox– type fiascoes and tens of billions in losses for the people who are gambling in an area where there is precious little to protect them. The smart money, meanwhile, should do fine, vulnerable only to its own hubris. ‘Everyone’s like, token sales are complete madness right now,’ [crypto investor Olaf] Carlson-Wee says. ‘I don’t think we’ve seen anything relative to how big this could be.’ ”

—Forbes, July 27, 2017

Spot on. The bubble burst within six months,

but it ended up looking downright tiny compared to today’s runup: Cryptocurrencies have swollen to a total market cap of $2.6 trillion— triple the 2017 bubble’s peak.