Donald Trump's callous attitude in France shows he needs the lessons of WWI more than anyone

Despite Trump's tweet, the French did not intend to ‘celebrate’ the war's end, but to commemorate, and indeed honour its victims. It is highly significant that a peace forum concentrating on international cooperation has been snubbed by the US president

Drawing lessons from how and why nominally civilised nations descended into all-out war should have been Donald Trump’s principal focus this weekend.

As the 45th president of the United States, the 72-year-old was quite rightly a guest of honour during French commemorations of the Armistice that brought the First World War to an end exactly a century ago.

It gave him a chance to turn his mind away from midterm election results, and – more generally – hugely divisive issues, ranging from immigration and nuclear proliferation to constant allegations of personal sleaze and corruption.

The head of state and America’s first lady Melania Trump get on surprisingly well with their French counterparts and hosts, Emmanuel and Brigitte Macron. When they were last in Paris together, the couples dined in an Eiffel Tower restaurant and posed for pictures at Napoleon Bonaparte’s tomb in Les Invalides. This time, meals were arranged in magnificent buildings including the Palace of Versailles, once home to France’s kings and queens.

The contrast between such ancient regime glories and starkly moving graveyards could have had a positive effect on Trump: persuading him to spend a bit of time contemplating what happens when diplomacy collapses.

It would certainly be difficult for most people to visit France’s numerous monuments to fallen soldiers without being humbled, but early indications are that Trump is exceptionally insensitive to the past suffering of his countrymen.

In an extraordinary show of callousness on Saturday, he cancelled a long-planned visit to the Aisne-Marne American Cemetery, next to Belleau Wood, where 1,811 US servicemen were killed in 1918. Trump blamed “bad weather” for changing his schedule, with his aides claiming that Marine 1 – the presidential helicopter – was incapable of negotiating the rain clouds covering the 50 miles from Paris to Belleau.

Trump was probably unaware that more than 1,000 Marines were killed or wounded at Belleau, but there appeared to be bloody-minded indifference in his decision to enjoy some downtime in Paris, instead of fulfilling his duty.

Or, as Nicholas Soames, the Conservative MP and grandson of Winston Churchill, put it on Twitter: “They died with their face to the foe and that pathetic inadequate @realDonaldTrump couldn’t even defy the weather to pay his respects to The Fallen.”

In another crass act, Trump caused further controversy by tweeting: “Is there anything better to celebrate than the end of a war, in particular that one, which was one of the bloodiest and worst of all time?”

Needless to say, the French did not intend to “celebrate” its end, but to commemorate, and indeed honour its victims. It is highly significant that a peace forum concentrating on international cooperation, and organised by Macron to coincide with the Armistice weekend, has been snubbed by Trump.

Macron has been alongside the Trumps throughout the weekend, following an entire week of personally paying tribute at war cemeteries around France. There could be few better guides: the 40-year-old was born and brought up in Amiens, capital of the Somme department, where some of the bloodiest fighting of the 1914-18 conflict took place. Macron’s great-grandfather George Robertson was, remarkably, a British Tommy on the Somme, while other family members fought for France.

Anyone who discusses such antecedents with Macron – as I have done – will find someone who is acutely aware of the fragile peace that so many of us have taken for granted during our lifetimes. He particularly credits the European Union for ensuring that former warring neighbours, and especially France and Germany, are no longer prone to attack one other.

Like Britain, France enjoyed a relative golden age in the run-up to 1914. The Industrial Revolution was transforming the country into a global commercial power, but soon it was providing the machinery used to massacre mainly young men in what was once prime agricultural land.

This profound sense of human failure is what comes to mind when you see the rows and rows of tombstones in cemeteries such as Aisne-Marne. They evoke images of every kind of person – all races and religions brought together in intense misery. Gas attacks, constant shelling and machine-gun fire created a world of horror that renders the vast majority of problems we complain about today almost irrelevant.

In terms of fatal casualties, America’s military sacrifice was relatively low. Some 115,000 were killed, compared to around 1.7 million for France and up to a million for the British Empire. Germany lost as many as 2.8 million, while the toll for Russia was even greater – their figure of three million plus deceased was a prelude to the Soviet Union’s gigantic Second World War struggle when at least 20 million citizens perished.

There was no Trump-style bellicose nationalism when America entered the war in 1917, however. On the contrary, the US then represented hope and optimism. As in the Second World War, the French saw the young country on the other side of the Atlantic as being a source not just of material wealth and manpower, but of being on the right side of history. These were the days long before hugely controversial military adventures such as Vietnam and a series of more recent interventions across the Middle East and Central Asia tore such a reputation to shreds.

Yes, America remains the world’s only superpower, and can out-shoot anyone, but – as Trump personifies – the direction of its moral compass has been severely jeopardised by years of meddling and muddling, often in a manner that can only be described as barbarous. If Donald Trump can learn anything from this weekend’s trip, then it is that world leaders responsible for crucial foreign policy decisions need to unite in solemn reflection. War comes quickly, and one of the best ways of avoiding it is to show some respect to its victims.