⚠ Europe Already Ran This ExperimentHigh threat

The European Union capped interchange at 0.2% on debit and 0.3% on credit in 2015. The networks did not collapse; they adapted, and Visa's European business has grown since. That is usually cited as evidence the threat is overstated.

It is better read the other way round. The caps established that a major economy can legislate the price of a private network's core product, survive the transition without disruption, and keep the rule permanently. Every regulator considering the same step now has a decade-long worked example, and the argument that capping interchange would break payments is no longer available to anyone.

What the caps did do was compress issuer economics and shift competitive attention toward the networks' own fees, which European regulators then examined as well - Visa still runs a dedicated retrospective responsibility plan for its European exposures a decade later¹. The direction of travel there has been consistent and one-way for ten years. The measure worth tracking is Visa's European yield against its American one: the gap is what a capped market looks like from the inside.