By Paul Reynolds
World Affairs correspondent, BBC News website
US mortar bombs can be both explosive and phosphorus
The Pentagon's admission - despite earlier denials - that US troops used white phosphorus as a weapon in Falluja last year is more than a public relations issue - it has opened up a debate about the use of this weapon in modern warfare.
The admission contradicted a statement this week from the new and clearly under-briefed US ambassador in London Robert Holmes Tuttle that US forces "do not use napalm or white phosphorus as weapons".
The official line to that point had been that WP, or Willie Pete to use its old name from Vietnam, was used only to illuminate the battlefield and to provide smoke for camouflage.
'Shake 'n Bake'
This line however crumbled when bloggers (whose influence must not be under-estimated these days) ferreted out an article published by the US Army's Field Artillery Magazine in its issue of March/April this year.
The article, written by a captain, a first lieutenant and a sergeant, was a review of the attack on Falluja in November 2004 and in particular of the use of indirect fire, mainly mortars.
It makes quite clear that WP was used as a weapon not just as illumination or camouflage.
"WP proved to be an effective and versatile munition. We used it for screening missions at two breeches and, later in the fight, as a potent psychological weapon against the insurgents in trench lines and spider holes where we could not get effects on them with HE [High Explosive]. We fired "shake and bake" missions at the insurgents, using WP to flush them out and HE to take them out," the article said.
In another passage the authors noted that they could have used other smoke munitions and "saved our WP for lethal missions".
A word about the term "shake and bake." Anyone with a family to feed in the US knows what this term, properly "Shake 'n Bake, means. Made by Kraft, it is a seasoning which is put into a plastic bag with chicken and shaken before before baking. Its use gives the article the smack of reality. It's the kind of thing US soldiers would say.
This tactic of forcing opponents out of cover is not new and should not really have come as a surprise. An article looking back at the Vietnam war published in 1996 by a US armoured unit (1st Battalion, 69th Armor)
referred to "Willie Pete" weapons and their use in getting North Vietnamese troops to leave their positions:
"Our normal procedure was to fire these things at a hillside as soon as possible in order to get them out of the fighting compartment."
One wonders of course if, in Falluja, WP was used more directly to kill insurgents and not just to flush them out. In battle, soldiers take short cuts and this seems an obvious one.
Evidence that this happened in Falluja comes from an article by a reporter, Darrin Mortenson of the North County Times in California, who was embedded with US marines there.
He wrote about a mortar unit receiving coordinates of a target and opening fire:
"The boom kicked the dust around the pit as they ran through the drill again and again, sending a mixture of burning white phosphorus and high explosives they call 'shake 'n bake' into a cluster of buildings where insurgents have been spotted all week."
The tactic therefore seems to have been not to flush them out first but to bombard them simultaneously with the two types of weapons.
Chemical Weapons Convention
The debate about WP centres partly though not wholly on whether it is really a chemical weapon. Such weapons are outlawed by the Chemical Weapons Convention (CWC) to which the United States is a party.
The CWC is monitored by the Organisation for the Prohibition of Chemical Weapons, based in The Hague. Its spokesman Peter Kaiser was asked if WP was banned by the CWC and he had this to say:
White phosphorous being used over Falluja
"No it's not forbidden by the CWC if it is used within the context of a military application which does not require or does not intend to use the toxic properties of white phosphorus. White phosphorus is normally used to produce smoke, to camouflage movement.
"If that is the purpose for which the white phosphorus is used, then that is considered under the Convention legitimate use.
"If on the other hand the toxic properties of white phosphorus, the caustic properties, are specifically intended to be used as a weapon, that of course is prohibited, because the way the Convention is structured or the way it is in fact applied, any chemicals used against humans or animals that cause harm or death through the toxic properties of the chemical are considered chemical weapons."
WP - the arguments
So WP itself is not a chemical weapon and therefore not illegal. However, used in a certain way, it might become one. Not that "a certain way" can easily be defined, if at all.
The US can say therefore that this is not a chemical weapon and further, it argues that it is not the toxic properties but the heat from WP which causes the damage. And, this argument goes, since incendiary weapons are not covered by the CWC, therefore the use of WP against combatants is not prohibited.
Critics claim that the US used chemical weapons in Falluja, on the grounds that it is the toxic properties which cause the harm. The UK's Guardian newspaper for example said: "The US used chemical weapons in Iraq - and then lied about it."
There is an intense debate on the blog sites about this issue.
"It's not a chemical weapon" says Liberal Against Terror.
"CONFIRMED: WP is a CW if used to cause harm through toxic properties," says Daily Kos.
Update 22 November: I have received an e-mail from a reader who points me to a reported US army document from 1991 which refers to WP as a chemical weapon. The document reports the possible use of WP by Iraq against the Kurds who rose up after the Gulf War. It says: "Iraq has possibly employed phosphorous chemical weapons against the Kurdish population."
The reader said this was proof that the US viewed WP as a CW.
I have also been contacted by Gabriele Zamparini of the Cat's Dream blog who appears to have published this document first. He makes the same point that the US Defense Department itself called WP a "chemical weapon." I offer these comments as part of the debate.
Tactical use of WP
The other argument is about the use of WP as a weapon.
The initial denials from the Pentagon suggest a certain hesitation, embarrassment even, about such a tactic. Some decisions must have been taken in the past to limit its use in certain battlefield scenarios (urban warfare for example). It is not used against civilians.
However the United States has not signed up to a convention covering incendiary weapons which seeks to restrict their use.
This convention has the cumbersome title "Convention on Certain Conventional Weapons." Agreed in 1980, its Protocol III covers "Prohibitions or Restrictions on use of Incendiary Weapons."
This prohibits WP or other incendiaries (like flamethrowers) against civilians or civilian objects and its use by air strikes against military targets located in a concentration of civilians. It also limits WP use by other means (such as mortars or direct fire from tanks) against military targets in a civilian area. Such targets have to be separated from civilian concentrations and "all feasible precautions" taken to avoid civilian casualties.
Notwithstanding the US position on the Convention, the use of WP against insurgents within Falluja does at least bring the issue into discussion, though one should note that the soldiers who wrote the Field Artillery article do say that their unit "encountered few civilians in its attack south".