Christopher Bellamy: These weapons may win the war, but leave a deadly legacy

British forces in Iraq have used cluster bombs against some Iraqi targets, Geoff Hoon, the Secretary of State for Defence, acknowledged yesterday.

America has not officially admitted their use, but it seems clear from television images and reports from "embedded" correspondents that large numbers of artillery shells and rockets containing submunitions or cluster bombs are being used. A necessary evil, under present circumstances, but while such weapons are the only way Allied troops can win without unacceptable casualties, the legacy of unexploded ordnance ­ the failure rate varies from five to 16 per cent ­ is alarming the aid agencies.

They are the ones who will have to ­ quite literally ­ pick up the pieces, perhaps for years ahead. More than 4,000 civilians are reported to have been killed or injured by cluster bombs in the aftermath of the 1991 Gulf War. In Afghanistan, civilians disastrously mistook the yellow unexploded bombs for food parcels.

The unexploded bomblets become, in effect, anti-personnel land mines.

Yesterday, humanitarian agencies were demanding they be treated as such. Cluster bombs are not specifically banned under the Ottawa convention which outlawed anti-personnel land mines, but their indiscriminate nature means they are often perceived as contravening the rules of war.

"Weapons affect tactics, which, in turn, determine their design." Carl von Clausewitz, the Prussian military philosopher who wrote that nearly 200 years ago, could not have imagined the US aircraft pounding the Republican Guard on the approaches to Baghdad. The Allies' artillery hammering the approaches to Baghdad and Basra would have just been recognisable, but the power of the improved conventional munitions now being fired would have been unimaginable.

The Allied forces have to use their exponentially increased firepower to defeat Iraqi forces, which they would never have dared take on otherwise.

That quantum advantage in firepower is the key to suppressing the three Iraqi Republican Guard divisions shielding Baghdad, and other Iraqi forces in the open. The key to that advantage is cluster bombs ­ the L20 artillery shells that Mr Hoon admitted have been used by the British against Basra ­ and the M26 warheads, which Human Rights Watch has said are fitted to the rockets fired from the multiple launch rocket system (MLRS).

Each M26 carries 644 "submunitions" ­ bomblets about the size of billiard balls. A typical salvo of 12 MLRS rockets would scatter more than 7,700 bomblets across 120,000 to 240,000 sq metres.

But as many as 16 per cent of these ­ 1,200 submunitions ­ may not go off, and would be left scattered across this considerable area. The American forces have also been using the army tactical missile system (ATACMS), a much bigger long-range missile, which travels in pairs on an MLRS launcher.

At least 18 of these missiles were fired in support of an attack by 101st Airborne Division on 28 March. The ATACMS missile carries 300 or 950 M74 submunitions with a failure rate of 2 per cent.

The L20 artillery shell, which a British military spokesman initially denied had been used in Basra, is a lot more reliable than the MLRS rocket, but is still not perfect. The dud rate is about 5 per cent.

The relatively new L20's submunitions have a back-up fuse, which has a second shot at detonating the bomblet after 15 seconds.

It is not clear whether air-dropped cluster bombs such as the BL755, which spreads 140 bomblets over a wide area, have been used in the air campaign.

Amnesty International condemned the British Government last night for using cluster bombs. Human Rights Watch has urged that cluster bombs should not be used in fighting near urban areas.

One interim solution might be for the American and British forces to make an effort to treat cluster munitions like mines, and carefully record all the targets attacked with them. That sounds a laudable sentiment, and might go some way to appeasing those who oppose their use, but keeping and maintaining such records in a fast-moving battle is easier said than done.

The legal and moral arguments about cluster bombs mirror those about depleted uranium anti-tank rounds, and new weapons such as the massive ordnance air burst (MOAB), and thermobaric (heat pressure) weapons, which suck air out of tunnels. All these weapons are, ironically, part of a quest for greater efficiency, to "weaponeer" the munition to the target.

Cluster bombs are particularly problematic because a lot of the submunitions do not go off. Those who developed them say they are not anti-personnel land mines, which are now banned, because they are not deliberately designed to blow up in that way.

The same argument affects laser weapons. Lasers deliberately designed to blind people are banned. Those designed to do something else, but which might blind by accident, are permitted.

Before being too critical of the Allies, consider two things. First, it is ironic that one of the Allies' biggest problems is protection of their long and vulnerable supply routes and bases. If anti-personnel mines were still legal, they would no doubt be sowing them in their hundreds of thousands. Second, if the new munitions can make the difference between a rapid end to the fighting, or months more of it, then their use will save far more lives than they threaten.

Christopher Bellamy is professor of military science and doctrine at Cranfield University