A scene from the film

War can be hell, even the bloodless war of a film festival. At Venice this year a dozen films of earthbound quality were fighting a ground battle for an elusive trophy when suddenly Samuel Maoz’s Lebanon, an Israeli war film, shot out of the ruckus like a rocket. Not the kind of rocket you see at a firework display. More the kind that comes straight at you from a military launcher, paralysing you with horror.

Brilliantly made and imagined, Lebanon won the Golden Lion for best film. It is, all else apart, an act of war on the Hollywood-style war movie tradition. In the aftermath of Inglourious Basterds, Maoz pulls us away from comic-book hokum towards the heart of blood and darkness: the interior of a four-man tank, a chamber pulsing with anguish and tension as its crew advances into danger during the 1982 Lebanon war. The violence and terror are felt close-up and personal: almost the entire film takes place inside the tank.

Maoz, a lean, wiry man, defends the film’s visceral approach. In the first war between Israel and Lebanon, in 1982, he was the gunner now reimagined as his movie’s lead character.

“I didn’t want the audience just to understand the story but to feel it. Because feeling is understanding. I want the audience inside the tank so they totally identify with the actors. You only see what they see, you only know what they know. What I asked from my designer ... was that we don’t just see and hear the experience of being there, we smell and taste it.

“As a soldier, I remembered, the relationship with the tank is never clear. On one side he’s your enemy, on the other he’s your friend because he’s protecting you. My first memory, when I tried to write the script, was of the smell, the smell of burning flesh. I first tried writing it six years after the war but I kept stopping because I couldn’t go on. On one occasion I wrote one page, then had to go to the toilet to throw up.

Samuel Maoz

“Then in 2006 I was watching news of the second Lebanon war and I thought, ‘In 25 years nothing has changed.’ I was very depressed, also, because I was 45 and thought I must do something with my life.” (His career, at that time, revolved mainly around directing commercials.) “I started writing again and suddenly I couldn’t stop. I felt like a rocket trembling before take-off. I wrote the script in four weeks.”

The film’s revulsion against the costs of war, physical and emotional, is powerfully conveyed. Might that not doom it with rightwing Israelis today – or with members of the hawkish hierarchy still surviving from 1982?

“I thought so, too. I remember the shame of that time if you were not a good unquestioning soldier. Like my hero, I was thrown into battle and colleagues would scream if you did not shoot immediately. If you did not kill the enemy, you were killing your friends. They washed our brains at school: it was right to kill and die for your country.

“But when we finished the film we test-showed it to some audiences not at all leftwing. And the reaction was quite positive. When you feel this story through the soldiers and their emotions you say to yourself, ‘If I had been there I would probably have done the same.’”

The depth and intensity of the empathy Lebanon inspires is a little frightening. Much of it is due to the performances. Lead actor Yoav Donat was coached for his role by being shut in a boiling hot metal cabin for several hours while Maoz and helpers beat it with iron bars or rocked it to and fro.

Asked if each episode in the film was copied from his own experiences, Maoz says: “The events are not important, the aim of the story’s events is to establish an inner state, the injured souls of the four soldiers.” The 1982 war was, he says, unprecedented in Israel’s history. “Ask yourself why there have been three films about that war [including the acclaimed Waltz with Bashir] and none about the six-day war. It’s because the six-day war, and Yom Kippur, kept their ground rules. Each army had its clear objectives, its own piece of land to fight over, its own uniforms. In Lebanon these rules didn’t exist. The war took place in neighbourhoods; the enemy wore jeans; someone with an overview knew what to do, I’m sure, but on the ground it seemed out of control. There was madness in the air.

“It’s a painful society, my generation, the children of that war. When I was seeking finance for the film I met a rich businessman with a fancy office and ... photos of his perfect family. And we were talking and suddenly I was hearing, ‘I was a gunner in Lebanon and they asked us to bomb some neighbourhoods and we said, ‘But there are people there.’ And they said, ‘No, only terrorists, and we started to bomb it.’”

There were people there, though, as they later learnt from casualty figures. “Then this man was starting to weep”, Maoz says, “and he was saying to me, ‘I am a coward, I am a murderer, I am nothing.’ This man who seemed to have everything. Inside he was crushed. In my generation, one in every four people is injured like this. And after my film they feel able to talk to me. Some of them don’t even talk to their own wives. They don’t know why they feel so angry, so confused.

“We are living in different times. People today, people my age and younger: it’s not the Israel of my parents who were children of the Holocaust and think we are still in existing danger. We are not in existing danger any more. We need to change things.”

Nigel Andrews is the FT’s film critic