Not far from the Bolivian city of Santa Cruz lies the curiously out-of-place Japanese farming district of Colonia Okinawa. Many of those living there are descendants of Okinawan farmers, forced off their land - by bulldozers or at bayonet point - by American soldiers in the 1950s. Some of the dispossessed were persuaded to make a new life in Bolivia. But when they arrived, instead of the fertile land they had been promised, they were dumped in the jungle where many died of hunger or unfamiliar diseases. Only the more fortunate made it on to Colonia Okinawa, now considered a model of Bolivian development.

This quirky footnote to Japanese (and Bolivian) history illustrates a broader point. Okinawa, a semi-independent kingdom until it was formally annexed by Japan in 1879, has always had a raw deal. Barack Obama, the US president, should ponder this fact when he arrives in Tokyo tomorrow against the backdrop of a messy tussle over an Okinawan base for US marines. He should know that there are three - not two - parties to any discussions about the US-Japan alliance, the half-century old military arrangement that has underpinned postwar Asian stability. Like Banquo's ghost, Okinawa hovers uncomfortably at the table.