The Second World War was one of the most devastating events in all of human history. For the men and women who lived through that war, the experience was often too overwhelming for conventional language to describe. Instead, they used religious or mythical imagery in order to make sense of the incomprehensible.

These images and ideas have remained ever since, and are the bedrock upon which the postwar order was built. But, now that the generations who lived through the war are dying out, the myths they lived by are also beginning to crumble. In the years to come, this will have repercussions for us all.

Perhaps the most powerful image to arise in 1945 was the myth of Armageddon. Victor Klemperer, the wartime diarist, said that the rubble of Munich in 1945 reminded him of the Last Judgement. Witnesses from Warsaw, Manila or Hiroshima used similarly apocalyptic language because they could find no other way to express the enormity of what they had seen. Even historians sometimes use the same metaphors: for example, Max Hastings’ bestselling history of the end of the war is entitled Armageddon.

For the wartime generations, this myth provided a valuable warning: never again should we allow ourselves to slide into global war.

Fighting their way through this apocalyptic landscape in 1945 were a trio of other myths – the hero, the martyr and the monster. Each nation has had its own versions of this trio, but the imagery has always been the same. Our heroes are all square-jawed and selfless. Our martyrs are all pure and innocent. And our monsters are violent and vampiric.

On a global scale – or at least in the West – these images were quickly boiled down still further into universal archetypes. Throughout the postwar era, the one hero that rose above them all was the American G.I., as depicted in dozens of Hollywood films. Opposite this global hero stood our global monster – the Nazi. Our universal image of the martyr, meanwhile, especially in the 1970s, 1980s and 1990s, was often ‘the Jew’. Since Jews belong to all nations, they were a martyr many could agree on, a symbol of us all.

For the wartime generations, these archetypes were symbols for right and wrong, and a template for action. The hero must behave like a hero, protecting the weak and standing up to evil wherever he finds it. For better or worse, this was how America became the world’s policeman after 1945, and the guarantor of peace in Europe.

The final great myth that came out of the Second World War was the myth of rebirth. Throughout Europe and Asia, religious and political leaders in 1945 spoke endlessly of resurrection and reconstruction. Germany called this era Stunde Null, or ‘Year Zero’ – the implication being that civilisation had been given the chance to start again from scratch. To this day, the Security Council chamber in the UN building in New York is dominated by a huge mural of a phoenix rising from the ashes of warfare.

Of all the myths to come out of 1945, this is perhaps the most important, because it was what gave meaning to the war. It was the prize given to heroes and martyrs, which made all their sacrifices seem worthwhile. It was also the idea that offered the villains of the war a chance at redemption.

This quintet of myths – the end of the world, the hero, the monster, the martyr and the final resurrection – resulted in the comprehensive story upon which our postwar world could be built. Now, sadly, the generations who built these myths are dying. With their passing, we are losing the glue that once held our international system together.

Over the past 20 years, each of these myths and archetypes has been losing its grip on the global imagination. Take the archetype of the hero, for example. Nobody truly believes in the Soviet war hero any more, and the British war hero has been compromised by his colonial past. Even the American G.I. is routinely criticised. The respect that Europeans once held for the ‘greatest generation’ has been undermined by more recent American behaviour, particularly threats to invade European territories such as Greenland. Put simply, the hero is dead. Did he ever really exist at all.

The same is true for the martyrs of the war. For decades ‘the Jew’ was our universal martyr, but now this symbol is also being undermined by critics of events in the Middle East. Criticism of Israel now regularly spills over into renewed hatred for Jews, with tragic consequences for Jewish communities all around the world. While historians try endlessly to remind people that ‘Israel’ and ‘Jewishness’ are not the same thing, much of the world has stopped listening.

Just as our universal martyr is being discredited, so, too, is our universal monster now being rehabilitated. The Nazis and their symbolism are no longer shunned in the way that they once were. Far-right ideology has been on the rise across the world over the past 20 years. Images and narratives that would have been unthinkable in the 1990s are now a routine part of political discourse – not only among trolls on the internet, but among mainstream political parties.

Even the myth of the rebirth after the Second World War now looks increasingly shaky. In the late 1940s and 1950s, the postwar West was built on a vision of increasing prosperity, technological progress and international collaboration. In recent decades all of these ideas have been undermined. Technological progress has been revealed as the driver of environmental damage. Prosperity has given way to massive income inequality. And all of our most important organs for international collaboration, especially the United Nations and its affiliated bodies, are now being systematically defunded, sidelined and ignored.

Where once the myth of ‘Armageddon’ was a warning from the past, nowadays it looks more like something that is looming in the future. In a YouGov survey conducted last year, 8,000 people across six western countries were asked about their attitudes towards the Second World War: 45 per cent of them said that they believed that a new world war was likely within the next five to ten years.

It is no coincidence that these attitudes and fears are so prevalent now. For the last 80 years we have lived with generations of people who had direct experience of the Second World War, and who created a story of that conflict to help guide us away from any repeat. The last of those generations is leaving us now, and they are taking their stories with them.

If we are to make it through the next 80 years without a major catastrophe, we will need to create new stories, built on hope for the future. We will need to find new, universally accepted heroes and a new template for good and evil in the world. Such stories are not merely for entertainment, they exist to provide structure to political beliefs and visions for the future. No coalition between nations and peoples can be built without shared values and, underpinning them, shared myths.

Until we can find a suitable story, populated by myths and archetypes that we can all more or less agree on, we need to cling to the old mythology, created by our parents and grandparents in the rubble of 1945. Because without such stories to guide us, we are on dark and stormy seas.