China has told Japan to respect the international order established after the Second World War. The trigger was Russian President Vladimir Putin's visit to Iturup, an island in the Kuril archipelago - territory Tokyo considers its own and over which Japan lodged an official protest.

"China insists that Japan respect the results of the victory in the anti-fascist war," the Chinese Foreign Ministry announced. The wording is carefully chosen: it does not argue over who has a claim to the islands, it reminds everyone who lost the war.

An eighty-year-old dispute, pulled out right now

The Kuril Islands are among the oldest unresolved territorial disputes in the world - because of them, Russia and Japan formally do not even have a Second World War peace treaty. Tokyo maintains the islands are historically Japanese. Moscow does not discuss it. None of that is new.

What is new is who is speaking up. Beijing has publicly taken Russia's side, while Russian officials Maria Zakharova and Dmitry Medvedev dismissed the Japanese statements as "politically irrelevant, insulting and legally void". When China and Russia pull the same historical card on Japan in unison, this stops being a dispute about a few rocks in the Pacific.

Historical argument is the handiest weapon in diplomacy precisely because it has no expiry date. Any dispute can be revived whenever it is needed, and nobody can close it with facts - because the facts are eighty years old and each side has its own.

Does any of this sound familiar? In the Balkans, history is rarely a matter for historians. It is a reserve argument, kept in a drawer and pulled out when current politics runs out of anything stronger.