TV review: The Iraq War, BBC2

Whatever else it has done, The Iraq War, Norma Percy's three-part history of the conflict and its aftermath, has greatly increased our understanding of diplomatic prevarication. Every colour in the spectrum of mendacity makes an appearance in these programmes, from the infra-red of the outright lie to the ultra-violet of polite euphemism.

My favourite from last night was the "fraternal visit", the phrase used by Jack Straw to describe the trip to Baghdad he made in the company of Condoleezza Rice. They'd gone to visit the then Prime Minister Ibrahim al-Jaafari, a man who'd disappointed the Americans by failing to quell the activities of Shia militias. And to be fair, al-Jaafari does seem to have been a bit of a disappointment.

After al-Qa'ida militants bombed the al-Askari mosque in Samarra – one of Shia Islam's holiest shrines – Jaafari was disinclined to impose the curfew that might have restrained revenge attacks. His reasoning was situated somewhere to the red end of the spectrum: "People want to vent their feelings, that's fine... In a democracy, people must have room for disagreement," he said. And, as he almost certainly knew would be the case, those disagreements were mostly expressed with a bullet in the back of the neck for scores of Sunni civilians.

The "fraternal visit" was designed to oust al-Jaafari and install some more congenial figure in the premiership, a mission that was naturally preceded by a press conference insisting that this was the very last thing that Straw and Rice had gone to Baghdad to do. Deciding who the Iraqi Prime Minister was going to be was, of course, the sole privilege of the Iraqi people. Then Condi softened al-Jaafari up with flattery and Jack went in and delivered some brotherly advice. We're supplying the security, he said bluntly, and we're supplying the cash. So resign now. Al-Jaafari, who could clearly recognise a horse's head at the bottom of the bed when he saw one, obliged.

Next man up was Nouri al-Maliki, chosen as the best of a bad lot by the Americans . Al-Maliki gained some momentary points for candour here with his description of the opportunity he'd been offered by the Americans: "Whoever agreed to be Prime Minister of Iraq would have to be adventurous or insane," he said. As sectarian killing mounted in Iraq, nobody on the Coalition side found it easy to decide which al-Maliki was, though his decision to fly to Basra and personally oversee the ousting of Muqtada al-Sadr's militiamen certainly tilted analysis in favour of insanity. "We thought it would be easy," al-Maliki recalled, a terrible phrase for a politician to utter, and one that should be inscribed on the tombstone of the some 170,000 civilians who've been killed since the invasion.

Like both previous programmes, this offered a depressingly detailed account of the failures of the war. Unlike the first two episodes, though, it brought that account of failure up to date, finishing with Obama welcoming al-Maliki to Washington and praising "Iraq's most inclusive government yet", immediately after a sequence that highlighted the increasingly totalitarian nature of his regime. The Americans got another strongman, but last month in Iraq was the bloodiest for five years, with 1,045 Iraqis killed in sectarian violence (two days before transmission around 70 people died in tit-for-tat bombings and murders).

In fact, this final episode did its job so effectively in exposing the hollowness of claims about the success of the war that it left you hankering for the one important journalistic component that has been missing from the series – simply because of the way it is constructed – tough and forensic cross-examination. Bring back Tony Blair and Jack Straw, you thought by the end, and force them to answer some harder questions. Really? Was it all worth it? For this?

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