EVERY TRIP I make to Jura I try and make a short pilgrimage to a lonely graveyard. It is the graveyard of a little community – first abandoned and now rebuilt with holiday cottages – just outside Craighouse and its graveyard is one of remarkable peace and beauty set in to the hills with a burn running beside it.

It is beautifully maintained and well known for its medieval slabs. This is not why I go to Keills. In there is set the gravestone of one family – I cannot even recollect the name – anonymous in their dates of life and death. But beside one name is this inscription: 1917 Passchendaele.

The contrast of this quiet graveyard in an abandoned community on a remote island and the blood and horror of the Western Front remains as sharp to me as the first time I saw it. Of course such inscriptions are not uncommon across Scotland but it is the sheer gulf of the contrast that hits home here, of the crofter who from a remote glen which he may never have left before going to lay down his life in Flanders to try and halt with many thousands of others the brutal juggernaut of the Prussian military machine.

In a rather different contex, at home at the bottom of my stairs is a photograph of a man on a camel, my grandfather in Mesopotamia in 1917. It’s a magnificent shot and my grandfather, as befits a leading light in the Renfrewshire Hunt, sits astride the camel quite comfortably. I never knew him. He died relatively young having never fully recovered from the effects of gas on the Western Front.

In reflecting on this it occurred to me that the SNP has made the most stupendous error in scheduling its referendum for 2014. Far more important for all of us than the 700th anniversary of a medieval stramash, important as indeed it is, will be the commemoration one month later of the beginning of the war to end all wars. A war in which Scots, English, Welsh and Irish stood together as one nation and one country against militarism and aggression, a war in which Scotland paid a terrible price in blood, amongst the highest casualties per head of population of any combatant, and a war whose consequences are with us today. That gravestone and that photograph show how near to us those days still are.

If I were David Cameron in 2014 I would allow the SNP their braying jingoism, their faux medievalism, and their distortions on history and then one month later I would come north and lay a wreath on that quiet grave on Jura, his favourite island and one where he holidays regularly. And I would simply talk about that one man in a lonely grave and what he symbolised.

And having done that I would move north to Inverness, to the Cameron Highlanders' memorial – now a club house – in Inverness, the regiment of his family, and speak again, not just about what we all share, not just about the strength of Scotland in its union with its partners but about his own family and how they represent what the union has given Scotland – coming south in the 1860s to work in banking with HSBC, working then with the Rothschilds before finally becoming senior partners in Panmure Gordon – the ‘lad o pairts’ made good.

And in quiet dignity commemorating not the false glamour of war but its terrible consequences, David Cameron could and should say much that needs to be said about the Union and what it means. By simple contrast the point is made.

And he could too say so much more. As Bannockburn will have been twisted into a great confrontation of Scotland and England rather than the clash of two feudal overlords, so he could point to the many lies and distortions that led to the Great War, of overweening German nationalism, of a history twisted into a false inevitability and to the belief that power conquers all. It is in speaking for the myriad dead that he can give the living hope.

It is an eloquent comment on the insularity of nationalism, its inability to see the world stage that in seeing Bannockburn they forgot the far greater commemoration that follows on. Let us hope that their opponents see not the threat but the opportunity that we have been given.