Can history play any useful role in helping us deal with the problems of today? It's an old teaser and the answer to it depends on many variables. Sometimes a knowledge of what happened in the past can be useful, especially if the lessons have been learned and digested, although that seems not to have been the case when the decision was taken to invade Iraq. Did anyone in Whitehall or the White House consider the ramifications of British and French meddling in the Middle East in 1917 or was any consideration given to the reasons for the bloodbath in Iraq in 1921? Probably not.

But there are times when the past can impinge on the present in an unhelpful way. If age-old enmities influenced current policies Britain would have nothing to do with France: since 1066 there have been 35 wars between the two countries and we've won most of them. (All right, the majority were fought by the English and Scotland was often on the losing French side, but the argument still stands.) That's why the issue of the Armenian genocide is such a vexed one and that's why such a big question mark hangs over last week's decision by a US Congressional committee to give it that status.

Nobody doubts that massacres on a huge scale took place between 1915 and 1917 when Ottoman forces systematically destroyed Turkish Armenia and killed an estimated 1.5 million (the exact figure is hotly debated). The orgy of destruction arose from a belief that the Armenians had been helping Tsarist Russia and the Ottoman government ordered the deportation of the entire Armenian population from the northeast provinces to locations outside Anatolia in the Syrian desert. Hundreds of thousands were killed or died as they made their way through the inhospitable environment and even the Turks' main allies, the Germans, were shocked by the high attrition rate.

On that score at least the incident fits the UN definition of genocide, which is described as any operation "intended to destroy in whole or in part, a national, ethnic, racial or religious group". In vain do Turkish apologists claim that the massacres were exaggerated by propagandists and there were sound military reasons for punishing a group of people who stood accused of lending assistance to the enemy. In an age when mass slaughter or attempted mass slaughter is regarded as a massive crime against humanity the Armenian genocide deserves its appellation.

So, there should be little fuss about what happened in Washington last week. Except that it was not just about correcting an historical wrong. The House Speaker Nancy Pelosi saw it is an opportunity to embarrass President George W Bush, who has already said that he will fight any attempt to put the matter to a full Congressional vote. He doesn't want to upset a major US ally at a time when the US is dependent on Turkey to support operations in Iraq. He has good reason to be concerned, as Turkey has already withdrawn its ambassador from Washington and is making threats to deny the US further use of the strategic air force base at Incirlik.

And this is where things get really murky. At stake are issues which go beyond the historical bickering over what happened 90 years ago. Today it's about dealing with a country which could quite easily destabilise the whole geo-strategic region. In what could be seen as a reprise of past events the Turkish military is making ominous noises about engaging guerrillas of the Kurdish Workers Party (PKK) who have been attacking their forces in southeast Turkey. Forces have been moved up in preparation for a cross-border strike and Turkish commanders are said to be in a dangerous mood, anxious to give the PKK a bloody nose.

If that were to happen it could be disastrous for Iraq, where the Kurds already enjoy considerable autonomy. With the Turks anxious to prevent any further expansion of Kurdish hegemony and the Kurds equally eager to reinforce their independence, there could be a showdown and the West would be powerless to intervene. The last thing needed by Iraq is a breakaway Kurdistan getting into a new confrontation with its touchy neighbours.

Turkey is now in that dangerous position where it feels threatened and boxed into a corner. Such a situation will only give comfort to the emergent nationalists who already believe their country has conceded too much ground to the West for nothing in return. First they were given short shrift in their application to join the European Union and now they stand accused of a genocide which happened in their great- grandfathers' generation. Historical insults have a nasty habit of breeding violence of mind: hitting back at the Kurds could just salve that wounded pride.