In the days ahead we can confidently expect a burst of fervour around the 70th anniversary of the D-day landings. But this will sit oddly with two other tendencies of the moment: first world war mania and the wave of Europhobia. By contrast with the comforting power of the D-day myth, we still do not know what to do with 1914. We are even less clear about our current position in the world, awash as we are with anti-Europeanism.

History is as much a matter of forgetting as remembering. In the current moment, it has become too easy to see the two world wars as wars of Britishers against Europe. The inconvenient truth about D-day for today's little Englanders is that fighting and winning the second world war was a horribly cosmopolitan business. Yugoslavs, Greeks, Poles, Czechs, Danes, Norwegians, Dutch, Belgians and French mixed and mingled, along with cohorts from all over the empire. Added to which the entire country was overrun by Yanks. For this multinational alliance, securing the UK's independence was not a goal in itself. It was a launching pad for a wider campaign to liberate the continent and to build a better Europe.

And lest we forget, this had also been the basic rationale for Britain's even more costly European engagement in the first world war. Amid the contention about the July crisis in 1914 and the mists of emotion concerning the Somme and the trenches, one can lose sight of the fact that Britain's war aims in the first world war were an admittedly self-interested blend of grand strategy and international liberalism: restoring Belgium, building a law-bound system for Europe which could square the security of France, Italy, Russia and a host of newly independent states in central and eastern Europe with the existence of a large and unified Germany.

As far as the Churchillians were concerned, the continuities between 1914 and 1944 were direct. They bookended a "second thirty years war". In 1944, British troops returned to where they had fought in 1914-18 and 1940 alongside the French. Churchill's sense of entanglement with France was so acute that in June 1940 he agreed with his cabinet to propose a Franco-British union. On the American side too, the sense of D-day as the culmination of a generational crusade was palpable. The commanders of the GIs who were struggling ashore at Omaha and Utah beaches had first set foot in France in 1917 and 1918.

Of course, not everyone agreed with this legitimising assertion of continuity. One of the truly remarkable things about Churchill's war government in 1940 was that it included three first world war-era conscientious objectors. Like many others in 1914, they had refused the moral case for the first world war. They did not want to see Britain line up behind resentful and aggressive France and autocratic tsarism. There were powerful strands of Europhobic isolationism among the British left who opposed the Great War. But Nazi Germany was a different type of enemy. Even to British isolationists, the blitz had taught that there was no hiding place.

But behind these clashing views of 1914, D-day and present-day Europe, one suspects that a more parochial concern lurks. If Blackadder is the benchmark of the disillusioned view of the first world war, then the war had nothing to do with the French or the Germans. They barely figure in the legendary episode. The war was a drama of British class relations, Upstairs Downstairs played out in the mud of Flanders. The image of donkeys leading lions compels us because it makes heroes of the salt-of-the-earth Tommies, at the expense of the braying upper-class twits who supposedly led them to their deaths.

The second world war, on the other hand, retains its place in the popular imagination as the people's war. The crusade to liberate Europe in 1944 carried the Beveridge report and Keynes's promise of full employment on it banners. By contrast, what is Europe today? Well, as we lazily let it be said over and over again, it is a top-down project of the metropolitan elite, easy meat for the populists.

Three different images of the first world war, the second world war and the present day map on to three different regimes of inequality. And, put in these terms, the link becomes obvious to another rage of the moment – Thomas Piketty's map of inequality under capitalism, which derives some of its best data from Britain. It shows inequality peaking in the era of the Somme and Passchendaele. It declined from the outbreak of the second world war down to the 70s. Just as Britain joined Europe, neoliberalism triumphed. Indeed, Britain contributed mightily to turning Europe into a vehicle for neoliberal market reform with all its attendant social side-effects.

One should not overdramatise. The impending decision on Britain's future in Europe is fateful but it is not as momentous as that taken in August 1914. On the longest day, 70 years ago, as the invasion armada bobbed around in the Channel, the future of the world was at stake. But the juxtaposition nevertheless casts depressing light on our current condition. The tensions unleashed within British society by the era of total war between 1914 and 1945 set the stage for a dramatic shift towards greater equality and inclusion. Right now we are heading in another direction altogether.

When the political class has lost its nerve to the point where populists' fears about Romanian immigrants can seriously menace our position at the heart of Europe, we are further away from D-day than the 70th anniversary suggests. In the menagerie of political metaphor there are no more lions, but plenty of donkeys, and they seem thoroughly spooked by the vermin in the trenches.