This quiet dignified film is blessed with an Oscar-worthy performance which displays precisely the same rare qualities, by the mesmeric Tommy Lee Jones. It is by far the best film so far to evoke the contradictory emotions personal, political and moral, that are and should be aroused by the Iraq war.

It is the most effective, even including the pretty good Charlie Wilson’s War. One mustn’t confuse the Afghan War with Iraq, but there is a sense in which they can be bracketed together as both are contemporary, unilateral invasions, part of the ‘War on Terrorism’ and in the same complex Middle East context. TVOE works so much better because Director Paul Haggis has understood that his prime objective is artistic truth not quasi-documentary verisimilitude. It is superior to other efforts: from the disappointing Lions For Lambs, the muddled Rendition, and the pretty dreadful My Kingdom and Syriana. It is also far more powerful in showing the moral and emotional impact of war on the young men called upon to put their lives on the line, than the more literal and documentary style of Jarhead.

Tommy Lee Jones is like a fine a wine, he just keeps getting better with age. This is his third fine performance in a row and caps even his powerful presence in both the present Coen brothers existential chase thriller, No Country For Old Men; and his own impressive directorial debut, the extraordinary Three Burials of Melquiades Estrada. What makes his ex-Army military criminal Investigator Hank Deerpoint so striking is that Lee Jones denies himself the immensely useful impact of his usual screen persona – ironic, sarcastic, laconically wry observer of the absurdities of people and their behaviour in a pretty messed up world.

Hank is much more pared down: a committed army officer still observing all the little personal rituals of army discipline from de-creasing trousers by dragging them over the edge of a chest of drawers, to putting on a shirt still wet from the wash rather than speak with Charlize Theron’s Detective Emily Sanders in his tee-shirt. Hank is disciplined, unsentimental, thoughtful and patriotic. He displays an emotionally coiled up character who is austere, distant and under iron control at all times.

Hank and his wife Joan, a small part but as ever, beautifully played by Susan Sarandon, are awaiting news from their son Mike just returned from a tour in Iraq. The army report him as AWOL but no one is much concerned as a couple of wild days unofficial leave time is common among Iraq returnees. But Hank soon becomes concerned because Mike has a good relationship with his parents and was in constant contact from Iraq. He heads for Mike’s unit but can’t get them roused. And he can’t get the police interested because an AWOL soldier is a military issue.

When a badly burned dismembered body turns out to be Mike, the jurisdictional dispute continues to hamper Hank’s search for the truth because the murder took place on the actual boundary of military and civil property; which side depending crucially on how well evidence at the crime scene is analysed. It becomes clear that the military want the matter hushed up and Emily has to battle her sexist cop bosses to get them to accept their responsibility of jurisdiction.

Displaying forensic and investigatory skills superior to both the military and all but Emily in the police department, Hank begins to shake the investigatory trees on both sides. Sympathetic to Hank’s loss, pissed at the pass-the-buck indifference of her own department she and Hank begin to work together, gradually unravelling a seedy story of sex, drugs and some undisclosed but sinister sounding events in Iraq involving Mike and his unit. Hank is helped by a corrupted video from Mike’s phone that a techie is painstakingly unscrambling piece by piece as the film progresses.

Gradually the witness lies and sweep-it-under-carpet evasions of both civil and military are peeled away by Hank’s good detective work aided by Emily. Hank’s dogged pursuit of the truth eventually yields rewards. But the truth proves an implacable friend and rocks the values and stability of Hank’s straight-line service-modelled private life to the core. His simple moral values recall the simple priorities memorably stated in A Few Good Men as, in order – Unit, Corps, Country, God. He begins to discover that the young men following in his Army footsteps, including his own son, with drugs, women and dirty combat practices reflective of a dirty, morally ambivalent war, are ignoring the deep values by which he has lived his life.

I guess Hank’s gradual loss of certainty, trust and conviction in all that he has always held dear, is a metaphor for America itself: bewildered by an implacable enemy they don’t understand; as in Vietnam, forced to fight a dirty war where the necessity of victory sanctions many things previously thought to be beyond the pale. This is a world where the concept of honourable warriors is obsolete. Torture as a necessity to save life is corrupted into torture for pleasure. The strength of Haggis’ film is to show rather than didactically describe this slide into immorality and loss of true military and human values, through the behaviour of the soldiers who are victims of the forces which generate it, but out of the combat environment. TVOE plays this out in full view of the law and parents who are ignorant of or turn their faces away from, the appalling moral pressures young soldiers face in a war like Iraq. We see the consequences on men’s minds, values and behaviour of all out war, where there are no non-combatants, even children.

Haggis’ impressive credentials as a writer (Million Dollar Baby, Monster’s Ball, Crash etc) are clear here both in dialogue and structure. He is manifestly a storyteller with a keen sense of plot and narrative. I suppose if the film has a weakness it is that after a powerful, indirect, resonant allusiveness throughout the film, Haggis ties his story up with an ending that is just a little too neat. However this ending is also very moving, visually strong and carries a potent sense of profound questions asked but not answered. So if it implies a tidiness at odds with the true story that apparently inspired it, his film does so for good and effective dramatic purpose.

The Elah of the title is the valley into which the Philistine Goliath daily challenged the Israelites to put someone up against him; to be felled famously by the boy, soon to become King, David. Hank tells this story to Emily’s son David clearly relishing a time of simple combat with accepted rules, courage and honourable outcomes. To add ambiguity of meaning Emily denies the truth of the story. But it is clear that with their absolute domination of straight power the USA are the Goliath’s of the Iraq war. While that works ok; I’m not sure who the David’s are.

Lee Jones commands the screen throughout and here with a character so emotionally contained that he succeeds only through consummate use of the almost imperceptible arts of screen acting; eloquent expressiveness of the eyes, tone of voice and the subtlest of facial expressions and physical movement.

This is for me a moving, exceptionally accomplished piece of traditional narrative filmmaking; supremely so in its central performance. In Oscar terms it perhaps lacks the innovation and sheer flair of say I’m Not There or the grandstanding style beloved of the Academy to deserve or contend for best picture. But if there is a better single performance on screen this year than Tommy Lee Jones’ Hank – I certainly haven’t seen it.