June 26, 1974 German regulators shut down Herstatt Bank while New York was still open the banks in New York had already wired the deutschmarks that morning the dollars they were owed in return never came back that one afternoon gave FX its most important hidden risk: Herstatt risk. you pay one leg of a trade and never receive the other CLS bank fixed this in 2002. it sits in the middle and only releases each side's money once both have shown up. clears $8T+ a day across 18 currencies if you trade EUR/USD or USD/JPY, you've never thought about settlement risk. the plumbing was rebuilt before you started but CLS only covers those 18 currencies most emerging-market FX (BRL, IDR, NGN, EGP, VND, and more) still settles the old way. you pay first and hope the other side comes through stablecoins can easily close this gap. when both currencies are tokenized, the swap is a single transaction with both transfers bundled together. it either completes in full or doesn't happen at all. in other words, atomic 50 years of FX plumbing compressed into one primitive, and we're just seeing the start of it today