Planting flags on islets, declaring cities where there are too few residents to fill a restaurant, and huffing and puffing over uninhabited rocks are acts more suited to a Gilbert and Sullivan farce than to nations in the 21st century.

Absurdities aside, the tensions in the South China Sea could shape the balance of power in Asia and put at risk the $18tn east Asian economy. However, a century-old diplomatic idea used by a former US president offers a solution to the crisis.

At present, things appear to be at an impasse. Legally, the overlapping territorial claims defy resolution – either through bilateral steps or through the Law of the Sea treaty. This treaty, to which China has acceded, rejects lodging “historically based” claims, which are precisely the type Beijing periodically asserts.