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Emmanuel Macron marked the centenary of the end of the first world war with a tour of the battlegrounds on which the war was fought. But the president of France is looking to the future as well as the past. Mr Macron issued invitations to more than 60 world leaders to mark the centenary in Paris. France has used the commemoration to launch a Paris peace forum under the slogan, "peace is linked with global governance."
But this mild message is unlikely to sit well with Donald Trump, who is an avowed enemy of global governance. The US president recently told the UN:
We will never surrender America's sovereignty to an unelected, unaccountable, global bureaucracy.
Mr Macron and Mr Trump represent two different traditions of thought about international politics, which clashed 100 years ago in Paris. Mr Macron's the heir to the high minded internationalism of Woodrow Wilson, the US president who personally represented America at the Paris Peace Conference of 1919. It was Wilson who set up 14 points to frame a new world order, and who wanted a League of Nations.
The League was to be a new form of global governance to end all wars. But Wilson's ambitious plans were shot down at home. The US Senate refused to approve American membership of the League of Nations, which went ahead without US participation. The opposition was led by Senator Henry Cabot Lodge, who explained, "I must think of the United States first," and said "internationalism is to me repulsive."
A hundred years later, the US now has a president who stands firmly in the tradition of Lodge, proclaiming America first, and proudly calling himself a nationalist.
We reject the ideology of globalism, and we embrace the doctrine of patriotism.
The peace efforts of 1918 and '19 failed, and war returned to Europe 20 years later. But internationalists like Mr Macron and nationalists such as Mr Trump drew very different lessons from that failure. For nationalists, the failure of the League of Nations has become a byword for the futility of global governance. In the 1930s, the league was totally unable to act as an effective check on the ambitions of imperial Japan, Mussolini's Italy, and Nazi Germany. In the end, it took the armies of nation states to stop the dictators.
But the internationalist response was that the really serious mistake was made by the likes of Senator Lodge. By snubbing the league and retreating into America-first isolationism, the US arguably created the conditions for international anarchy to flourish. So there it is. Trump v Macron, nationalism v internationalism. This is a debate that's even more about the future than the past. Which of these two ideologies will prevail? Come back to Paris in 100 years' time, and perhaps we'll learn.