Why stablecoins are Silicon Valley's Pandora's box

President Trump’s signing of the GENIUS Stablecoin Act marks a chapter in an ancient storyline—the eternal tension between progress and order. Pandora's jar—mistranslated as a box—came with strict instructions never to open it. Stablecoins also arrive with promises and prohibitions.

The warnings are mounting about the Pandora's box of problems that stablecoins will unleash. The economist Barry Eichengreen, one of the leading experts on the history and development of money, invokes the spectre of coins slipping their pegs to the dollar—as happened in 2022—and recalls the chaos of the free-banking era, when dozens of regulatory systems produced banknotes trading at wildly different prices. Yet this is perhaps the least urgent danger lurking inside.

It is likely that only a few stablecoins will dominate. Despite piggybacking on the dollar and often sharing the same blockchain, out of the box their smart contracts remain stubbornly non-interoperable and therefore non-fungible.

Each coin is a brand—and combined with the network effects inherent in money itself, winner-takes-all dynamics emerge. Already, two giants rule: Tether commands a $159 billion market capitalisation - 61% of the market - while Circle's USD Coin holds $62 billion or 24%.

Say what you will about the banking system, but it resists the extreme concentration that defines Big Tech. In spite of years of consolidation, the US still has more than 4,000 banks. Europe has more. That is because, up to now, banks have made a business of a private means of payment but to an open public standard. The result is a monetary commons—a seamless blend of commercial and central bank money that, in normal times, the public can't distinguish between.

Read the rest of this essay on the profound and mutiple problems with Stablecoins I wrote with Andreas Dombret, formerly on the Deutsche Bundesbank board and the supervisory board of the ECB.