Banks, meanwhile, aren’t missing the opportunity to redesign payment networks using old-fashioned dollars. Zelle, an instant-payment system run by a consortium of big banks, ran $187 billion of traffic last year, putting it well ahead of PayPal’s Venmo. Zelle is mostly aimed at retail clients doing things like splitting dinner tabs, but has handled transactions as large as $3.2 million.

No question, disruptive technology is coming to the banking system, and Coinbase will be a part of it. It is the only outfit to appear on both the Forbes Fintech 50 and Blockchain 50 lists. But Armstrong is going to have plenty of competition, starting with central banks, which are plotting their own digital currencies. Facebook hasn’t given up on Libra, which is intended to be a globally accessible digital currency backed by assets like dollars and euros.

Let a thousand flowers bloom, says Armstrong. “When I started Coinbase, most people thought [blockchain] was crazy. Governments and the old guard, the blue chips, are now investing in this technology. So let’s just say that’s a very good thing.”

Cover Photograph by Jamel Toppin for Forbes

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