In 2018, European officials watched President Donald Trump blow up a nuclear deal with Iran, reimpose sweeping sanctions and mull disconnecting its banks from SWIFT. They had had enough. America was using its financial hegemony to muscle allies into punishing its latest victim. European firms were fleeing Iran for fear of secondary sanctions from America.

Britain, France and Germany decided to put up a fight. Their answer was the “Instrument in Support of Trade Exchanges” (INSTEX), a barter system that could support humanitarian trade with Iran without any recourse to the dollar. Seven more EU states signed up. In March 2020 INSTEX’s inaugural transaction supported a sale of medical goods to Iran.