It's a war that never ends – cinematically speaking, that is. The second world war may have ceased hostilities on 2 September 1945, with the formal surrender of Japan in a ceremony on the USS Missouri, but the film world has never stopped fighting. Nearly 70 years on, the demand for second world war movies appears unstoppable, the supply inexhaustible. Last year saw the release of films about Germany during the war (The Book Thief), British soldiers imprisoned by the Japanese (The Railway Man), and the confrontation between Nazi and Soviet forces at Stalingrad (Stalingrad). By the end of 2014 we will have had films about the race to recover stolen artworks (The Monuments Men), a US tank crew fighting their way across Germany (Fury), a US soldier who survived shipwreck and a PoW camp (Unbroken), a biopic of pioneering codebreaker Alan Turing (The Imitation Game) and a fictional account of the German occupation of France (Suite Française).

Some movie wars – Vietnam, the cold war, Iraq – come and go, but 1939-45 just won't fade away. It's impossible to come up with a definitive list but, for comparison, Wikipedia's list of films about the 1914-18 war totals a little more than 130, while the same source's compilation of second world war films comes to more than 1,300, and still counting. A decade-by-decade breakdown tells a slightly more nuanced story: there were more than 250 made before the war even finished, reaching over 300 by the end of the 1940s; there were more than 200 each in the 1950s and 60s, before numbers started to decline in the 1970s (130-plus) and 80s (120-plus). The 1990s saw a relatively paltry 86 before a resurgence in the 2000s (180). The 2010s have seen more than 50 so far, suggesting we are on course for a similar figure this decade.

There are obvious reasons for the sheer mass of material, as well as its Godzilla-like dominance of the war-movie genre. The war itself, a gigantic conflict that played itself out in a myriad of theatres across the globe, that traumatised entire societies and triggered seismic political, technological and ethical upheavals, has almost endless potential for storytelling: there are little-known military exploits to recount, reassessments to be made, newly significant relationships to be detailed. Author Frank Cottrell Boyce, scriptwriter of The Railway Man, makes the point that the huge amount of second world war films has created its own momentum. "It reached a tipping point at some time. The war has become a metaphor, not just history. You can map on to it any way you want." Boyce ascribes its resonance to the perceived simplicity of the second world war's gladiatorial conflict. "We're attracted to it because of its moral certainties. Try explaining the cold war to kids: it was about a metaphysical geography of Europe that has completely vanished. But they have no problem grasping what the Normandy landings were about."

Why there should be a surge of interest in movies about the war since the 90s' (relative) trickle is a moot point. Cottrell Boyce suggests that, since 9/11 and the Iraq war, rather than seeming a "remote" issue, "war is how we do business now". For Matthew Sweet, broadcaster and author of The West End Front, it's equally to do with what he calls "a growing sentimentality about the war". "It's the generation that had initially ignored their grandparents' war stories, but now have those Keep Calm and Carry On posters stuck up in their office cubicles, or who have bought those Boden union jack bags. It's a sentimentality that allows people to pursue a dream of the war, and which enables their fantasies and preoccupations about it. I'm afraid it's a very empty engagement."

Quentin Tarantino's Inglourious Basterds, in which Hitler is blown up and a roving band of Jewish soldiers mercilessly take out sneering Nazis, is a key example of this kind of war movie – "a fantasy of how the Holocaust should have worked out", according to Sweet – but there are plenty of others. The Reader, on some level, is a fantasy that concentration camp guards can be unfairly scapegoated. The King's Speech, for all its virtues as a character study, implies that a single radio broadcast can alter the course of history. The Monuments Men suggests that locating looted artworks is a rambunctious, high-speed activity conducted by drunks and mavericks. Saving Private Ryan – released in 1998 and arguably the totemic ancestor of the wish-fulfilment second world war movie – concluded that the US army fought and won the war on its own.

Is it a coincidence that these films achieved a release in the era of regime change, CNN and Call of Duty? Moreover, these films also fulfil one of the basic functions of the second world war movie: to blow every previous second world war movie out of the water, or at the very least, torpedo them below the waterline. "These movies are a way of recuperating and recovering memories," says Sweet. "They're an attempt to fix an idea of the war. I suspect Steven Spielberg's version of D-day will be the one in people's heads in 300 years' time, in the same way that we think of the Russian revolution through Eisenstein's films. It's almost like a grab to produce the official version."

This is certainly not a new phenomenon: Sweet dates this kind of blot-everything-else-out kind of war film back to the Guy Hamilton-directed The Battle of Britain from 1969. In fact, we can broadly understand the evolution of the second world war movie as a process of redefining the war's meaning. During the war itself, of course, films tended to be patriotic flagwavers and somewhat hazy accounts of derring-do – in Sweet's description, "a way of prosecuting the war while it was actually happening". (This includes everything from In Which We Serve to I Married a Nazi.) When it was all over, the war movie became a way of trying to make sense of it all – "establishing a narrative we could all agree on". This sense of shared achievement began to evaporate by the late 1950s: films such as Bridge on the River Kwai began to undermine the sense of moral certainty around the war, that the picture was more complex. Perhaps the most engaging of second world war films – Where Eagles Dare – is identified by Sweet as part of a late-60s rightwing reaction against the prevailing counter-cultural mood – "all the characters could have been involved in the plot against Harold Wilson"; moreover, you can see how 60s war dramas such as this were the prototype for the action movie genre that was to emerge in the 80s.

Be that as it may, the second world war movie has bounced between a desire for documentary exactitude and historical revisionism; uncovering new details and reconfiguring the old ones. Hence the last decade and a half has seen a string of films attempting to tectonically shift basic assumptions of the conflict. In 2004 Downfall, for example, sought to develop the idea that not all Germans were fanatical Nazis. Defiance, a Daniel Craig film from 2008, attempted to counteract the idea that Jews failed to fight back. Roman Polanski's The Pianist suggested the essential kinship of the sophisticated music-loving German and the persecuted Holocaust victim. Ang Lee's film Lust, Caution focused on the moral compromises endured by the Chinese under Japanese occupation.

These are films looking to make grand statements about the war, and widen the focus of the traditional Anglo-American military-action setting. But there are smaller-scale efforts too: whether it's the contribution of Czech airmen to the Royal Air Force (Dark Blue World), the gruesome vengeance visited on partisans in the Soviet Union (In the Fog), or the difficulties faced by Algerians aiming to help liberate France (Days of Glory), film-makers have repeatedly ransacked the archives for material. The arthouse sector – say, The Sun, Alexander Sokurov's study of Japan's wartime emperor Hirohito – is just as likely to offer new detail as a star-led behemoth, such as Valkyrie, containing Tom Cruise's portrayal of failed Hitler assassin Claus von Stauffenberg. It helps, however, that the stories are not simply backward-looking: Days of Glory, for example, helped end discriminatory pension arrangements for surviving Algerian soldiers, while Cottrell Boyce is convinced that the torture scenes in The Railway Man, in the wake of Abu Ghraib, helped make the film "zeitgeisty".

Another consideration is simply that time is running out; nearly 70 years after the war ended, the number of people with firsthand experience of it is dwindling fast. In Cottrell Boyce's opinion, "it's our last chance".

You would, of course, think that there are simply no stories left to film, nothing more to say. But the upcoming schedules prove us wrong. There have been plenty of Hollywood movies featuring tanks, but Fury's selling point, no doubt, is its writer-director David Ayer's ability to engage with the macho dynamics of a small group of men (see his earlier films Street Kings and End of Watch, both about police officers). Suite Française is a natural for adaptation, being a war-set novel only recently rediscovered and published in 2004. And, as the central figure of The Imitation Game, Alan Turing is a figure of considerable interest, only recently officially rehabilitated and the spearhead in a new interest in the war from a tech perspective. The conveyor belt simply will not stop.

So can this obsession – addiction, even – to the second world war movie ever run its course? Over the decades, the war has penetrated every area of the cinematic universe, from cheapo sexploition (Ilsa, She Wolf of the SS) to retro-noir (Steven Soderbergh's The Good German) to the gormless Michael Bay blockbuster (Pearl Harbor). Superhero movies have co-opted it, in the Auschwitz-set prologue to The X-Men; monster movies have invoked it, with the rumbling menace of Hiroshima behind the original Godzilla movie.

Sweet thinks the second world war movie will prove extremely tenacious. "Vampires never existed and they won't go away," he says. "Until a new large-scale conflict comes along that can be viewed in comparably Manichean terms, the second world war will have its place."