Richmond accelerated ahead of the lead Humvee and waved it down. There was no sense using horns out in a high-risk zone.

Concerned the convoy had no active firepower in the rear, Richmond ordered the tail Humvee into the middle. Now he and Ashe would bring up the rear. Ashe would be able to concentrate on lookout duty.

In front of them: Sergeant Bolton and Ibrahim the interpreter – a weak link in the chain. In the lead vehicle: Corporal Pinsker driving, Zappa and Private Laski on the big gun, and Private Dykins behind the M249 squad automatic.

If Richmond entertained doubts about the suitability of the firepower for the mission at hand, he kept them to himself, telling Ashe that convoys like this were known ‘in the trade’ as porcupines: too prickly to be messed with. He’d made that up on the spot.

Ashe eyed the shimmering thread that hovered between earth and sky: nothing. Then he noticed a speck – a black speck in the distance. Mangled by heat-haze, the speck grew in size. Behind it, distantly, he could see what looked like a grey band on the horizon – maybe a distant mountain, or an in-coming storm.

‘What’s that speck?’

‘I can’t see it, Toby. I’ll drop back a bit.’

‘It looks like… maybe a distant mountain.’

‘How far?’

‘I don’t know. Maybe sixty or seventy miles.’

‘You’ve got remarkable eyesight, Toby. But it can’t be that far. It’s probably the Jebel Sinjar.’

‘Sinjar? As in Shinar?’

‘What’s Shinar?’

‘It’s the land where Noah and his lot came down to after the Great Flood. It’s where Nimrod built the Tower of Babel.’

‘Where all the races were divided?’

‘Yeah.’

‘Interesting. Come to think of it, from a distance, Sinjar does look a bit like the base of a massive ancient tower. It’s an amazing place. A bit like Ayers Rock in Australia. Only far bigger. A little mountain range popping up out of nowhere. You got flatland, flatland… nothing; then: Bang! Jebel Sinjar.’

‘Easy on the bangs, Simon!’

‘Still a bit jumpy? That village I mentioned – the one under attack – that would be up in the Sinjar. That’s where you’ll find our choppers.’

‘Comforting.’

‘As for the speck, I’ll bet it’s an oil derrick. There’s a drilling outpost at Tel Afar. Very close to the underground pipeline that runs south from Silopi, just over the Turkish border.’

‘Turkey? We’re that close?’

‘The pipeline runs south through Qayyarah West, just south of here.’

‘Wasn’t there a car bomb attack on the US facility at Tel Afar in December?’

‘Right. About thirty wounded. Could have been much worse. The guards did their job: approached the bombers and alerted the base. Even so, the suicide bomber detonated himself.’

‘And the bomber? Local insurgent or Ansar al-Islam?’

‘Tricky question, Toby. Last September, there was a new group announced.’

‘Yeah, I remember. Ansar al-Sunna. Defenders of the Tradition.’

‘Right. These guys are the main problem at the moment – at least in my sphere.’

‘What happened to the old group, Ansar al-Islam?’

‘Not entirely clear. Ansar al-Islam were mainly up in the Kurdish mountains northeast of here. Around Khurmal near the Iranian border. They threatened the Patriotic Union of Kurdistan forces, who are pro-democracy and modernisation, so they’re aligned with the Coalition. In March ’03, PUK peshmerga and US special forces mounted a joint op. You know how peshmerga vow to fight to the death? Well they pretty much took the Ansar al-Islam fighters apart. We thought we could rest a bit while the PUK exploited the gains.’

‘And now?’

‘To be honest, situation’s much worse. Ansar al-Sunna forces have been creeping back across the Iranian border in the hundreds. Corrupt Kurdish guards have been taking bribes. And they’ve been moving into Mosul, merging with the population, and working as fixers for al-Qaeda-backed operatives coming in from the western border with Syria.’

‘So you’ve got Ansar al-Sunna to the east of us, and al-Qaeda volunteers to the west of us. You could say we were—’

‘In the middle of things, yes.’

‘Shit.’

‘Hmm… And then there’s the problem with the reconciliation policy.’

‘The what?’

‘A nice idea. Major General Peter Atraeus, commander of the 101st Airborne, thought it might be wise to reintegrate some old Ba’athist Iraqi commanders – get them to work with the Kurds for the common good.’

‘As you say, a nice idea. Bad in detail?’

‘Maybe. The major general gave Syrian border security to General Muhammad al-Shiwah. He’s a member of the al-Shammari tribe. The tribe spans the frontier with Syria. It’s generally seen as being sympathetic to Saddam.’

Ashe observed how the speck seemed to be changing, like it was being smudged out, enveloped, yet somehow getting taller and taller.

‘Whatever the reason, Toby, we’ve now got a fairly porous border, with al-Qaeda-stimulated volunteers coming in from both sides and Ansar al-Sunna as the welcoming committee.’

‘That speck’s getting bigger. There’s a… what is it?’

Richmond reached into the glove compartment to his right and pulled out a telescopic sight. ‘Don’t bother mounting it on the M4, just tell me what you see.’

Ashe adjusted the focus. ‘It’s a… pillar of smoke.’

‘Must be a mistake.’

‘No, it’s on fire.’

Thoughts raced through Richmond’s head and they all crashed into one simple conclusion. ‘They’ve hit the pipeline.’