In a sector like aircraft manufacturing, where subsidies are ubiquitous,
it has always been clear that America and the EU needed to agree to mutual disarmament.
Instead, they have talked past each other, each complaining at various points that the other was unwilling to negotiate.
Most recently it has been the EU that has submitted proposals to America, only to be rebuffed.
Meanwhile, the boxes have been piling up and the lawyers raking in fees.
The Trump administration wasted no time in starting the formalities at the WTO that will allow it to apply the tariffs.
That means the EU can expect tariffs on October 18th.
As well as tariffs of 10% on large aircraft and 25% on agricultural and industrial goods,
the list the USTR published on October 2nd included Italian Parmesan, Scotch whisky and German waffles.
Even if a product is not on the list it may still be hit, as items could be shuffled in and out.
For all the fuss the dispute will generate among connoisseurs of European cheese, the biggest impact will be on aircraft,
of which America imported $5.1bn-worth in 2018, mostly from France and Germany (the USTR has said that only a portion will be hit).
It could have been worse—the Americans could have applied a tariff of up to 100%—but even one of 10% will bite.
American airlines fear that tariffs will raise the price of Airbus aircraft, and that Boeing will lack the capacity to expand supply.
Perhaps the WTO will find that the EU has removed its subsidies, and the Americans will stand down.
Or in eight months'time, when the WTO authorises the EU to place retaliatory tariffs on American imports as part of the Boeing dispute,
the two sides might finally negotiate away their differences. By then Mr Trump's appetite for tariffs may have been sated,
and he might abandon separate threats to put tariffs on European cars and car parts.
But it is also possible that trade disputes between the two sides become fiercer.
America is blocking the appointment of judges to the WTO's court of appeals.
If either side makes a move that the other judges an infraction, and a complaint to the WTO cannot be heard for lack of judges,
that could be the end of playing by the rules.