Shortly after Christmas 1914 an order was issued by John French, the general in charge of the British troops on the Western Front. He had heard of the informal truce that had broken out along the front on Christmas Day and ordered that such events must never be repeated. Just under a year later, ahead of the following Christmas, soldiers were told that they would be charged with disobeying orders if there was another truce.

The Christmas truce of 1914 varied along the front. The frequently mentioned football matches may have happened in only a few places. More commonly, soldiers met in no-man’s-land, chatting, shaking hands and swapping food.

After the war, John French conveniently forgot that he had issued orders against truces. He instead spoke of the Christmas truce of 1914 as an example of soldierly chivalry. He absurdly claimed that “soldiers should have no politics” — as if sending thousands to their deaths was somehow an apolitical act. 

Pro-war politicians and commentators today also tend to talk positively about the Christmas truce, as if it were an innocuous fluffy event that we can all celebrate. 

William Windsor, Duke of Cambridge, is one of the judges of a children’s competition to design a Christmas truce memorial. Super-wealthy Premiership football clubs are funding events to celebrate the footballing side of the truce. 

I suspect the government, the Premiership and the Windsor family would take a rather different view if British soldiers had chatted and exchanged food — and even played football — with enemy soldiers in Iraq, Afghanistan or the Falklands. 

It’s much easier to celebrate a controversial event a century after it’s happened — especially if you persistently ignore the reality that it was a rebellion against war. 

Of course, the left and the anti-war movement can fall for the trick of romanticising the Christmas truce just as much as the militarists. 

As the anti-war historian Adam Hochschild points out, this was not a case of working-class soldiers suddenly rejecting war. Officers up to the rank of colonel participated in the truce. Most of the soldiers obediently went back to fighting the next day. 

Nonetheless, the spontaneous truce must have undermined the propaganda of each side’s government, which sought to portray the soldiers on the other side as inhuman fiends. 

When people meet their enemies and discover how much they have in common, they become a threat to those who want them to fight each other.

This became apparent later in the war. After the fall of the tsar, Russian soldiers engaged in truces with Germans and Austrians that lasted longer and were more explicit in their politics. Pictures survive of Russian and German soldiers literally dancing together in no-man’s-land. 

The same principle holds true today. When Israeli Prime Minister Benjamin Netanyahu was talking up war with Iran in 2012, a group of anti-war Israelis set up a Facebook page called Israel Loves Iran. They told the Iranians: “We love you. We will never bomb your country.” They told the Israeli government they were “not ready to die in your war.”  

Iranians responded with a similar Facebook page called “Iran Loves Israel.” One of the first people to post on it told the Israeli people: “I don’t hate you. I don’t even know you.”

Thus people in “enemy” countries see that they have more in common with each other than with their own rulers. 

The question we should all be asking is the question asked by Keir Hardie, the socialist and pacifist MP, when he heard about the Christmas truce a century ago. 

“Why are men who can be so friendly sent out to kill each other?” he asked. “They have no quarrel … the workers of the world are not ‘enemies’ to each other, but comrades.”

There has been much criticism of Sainsbury’s this year for using the story of the truce in their Christmas advertisement. I had expected to be annoyed or angered by the advert, so was surprised when I first viewed it.

Of course, the advert exists to make sales for an unethical corporation. It also raises funds for the Royal British Legion who, while they do work to support British victims of war, continue to promote militarism and a pro-war view of history. 

The advert was not made to draw attention to the futility of war. Nonetheless, this is to some extent what it does. After they have shared food and played games, the soldiers depicted in the advert return to their trenches and continue firing at each other. Some of the people who have watched the advert must be asking themselves why.

The Christmas truce of 1914 was a spontaneous event. It was not explicit disobedience, as the orders against such truces had not been issued at that point. It was, nevertheless, a rejection of the propaganda that demonised the enemy. It was not a mutiny as such, but a sort of informal rebellion, celebrating common humanity over the demands of militarism and nationalism. 

No wonder the generals on both sides were worried. If they had kept on “fraternising,” these soldiers might have brought the war to an end. 

So let’s ask everyone the obvious question that most of the celebrations will ignore: If it’s acceptable to play football with someone on Christmas Day, why is it OK to shoot them on Boxing Day?