Already once delayed, the deadline for the imposition of steel and aluminium tariffs by the Trump administration approaches again. By June 1, the White House says, it will decide whether to start levying the duties — ostensibly for the protection of national security — and on precisely which products.

Some countries have already secured exemptions, most comprehensively South Korea. Seoul has agreed to tweak its bilateral trade deal with the US, and to a quota on Korean steel exports to the US. But the most high-profile trading partner, and the one which could set the tone for a global response, is the EU.

The European Commission’s initial response was suitably defiant, saying it would not offer concessions in a negotiation until the threat of these tariffs was permanently lifted. It also published a list of US products on which it would impose tariffs in return.