White phosphorus is an easily produced compound that has numerous military applications. It burns brightly and persistently. In battle, it can create a smokescreen that can hide troop movements.
These uses are not objectionable but the status of white phosphorus is complex. It is not normally used offensively, though it sometimes is employed as a makeshift weapon. When this happens, it can be dangerous.
White phosphorus burns at a very high temperature and, if it gets onto skin, it cannot easily be removed. It can cause terrible burns. If inhaled, it can do long-term damage to the lungs.
Hamish de Bretton-Gordon, a former British Army officer and currently an adviser to the Kurdish peshmerga, said: ‘If you get white phosphorus on you it’s almost impossible to put out. If you put water on, it burns more violently’.
Its use is therefore controversial and often criticised.
There have been allegations that white phosphorus has been used in Iraq and Syria, including the battles to liberate Mosul and Raqqa from the Islamic State (ISIS). This has been reported on negatively, with the use of white phosphorus being held against the international coalition and the local partner forces whose troops fight ISIS on the ground.
‘No matter how white phosphorus is used, it poses a high risk of horrific and long-lasting harm in crowded cities like Raqqa and Mosul and any other areas with concentrations of civilians’, said Stephen Goose, arms director at Human Rights Watch. ‘US-led forces should take all feasible precautions to minimise civilian harm when using white phosphorus in Iraq and Syria’.
The battle for Mosul has seen rates of civilian casualties that have caused concern. Tactics employed by the international coalition, involving the extensive use of air strikes, have drawn extensive criticism. Part of this is due to the nature of the Mosul battlefield, the city serving as a prison for hundreds of thousands of civilians who are trapped in the face of the Iraqi offensive.
At the same time, the narrow streets of the Old City made urban warfare bloodier and the fighting more difficult.
Those conditions also make the use of white phosphorus controversial. The trapped civilian population of Mosul, effectively confined to a few square miles, is more vulnerable to chemical changes in atmospheric conditions.
Dan Kaszeta, a former US Army Chemical Corps officer now working as a security and terrorism consultant, said: ‘There are reasonable and time-honoured legitimate military uses for [white phosphorus].’
‘It is, even to this day, gram-for-gram, the most potent way of creating large dense clouds of smoke for obscuration purposes on the battlefield and there are many tactical uses for smoke screens,’ he said. ‘In particular, [white phosphorus] is useful in that it blocks not just visible light but also scrambles infrared. This means things like thermal vision, targeting lasers, night vision, etc., are blocked by it as well.’
This extra dimension is particularly useful in fighting ISIS, which has shown a propensity for military innovation, from the home-spun and rough-edged to the notably advanced. ISIS’s use of drones, some equipped with thermal cameras, to scout Iraqi positions is well known.
In Mosul, drones can be used offensively – equipped with grenades – or for reconnaissance. White phosphorus munitions can minimise the effect of such murderous inventiveness.
This provides motivation for the Iraqi military, which has suffered high casualties while fighting ISIS, to make use of white phosphorus to shield its troops from observation. The international coalition must have known about such uses and would have licensed it in some way.
This presents its own problems.
Kaszeta said the use of white phosphorus is legally complex. ‘Despite the various things you may read, international law does not consider it a chemical warfare agent. It is not a scheduled (i.e. prohibited or restricted) chemical under the Chemical Weapons Convention’, he said.
Its legal status ‘depends on usage and intent’. If white phosphorus is used solely for ancillary reasons and not offensively, its use is not only defensible but tactically sound.
‘I think it is strategically justified but it is treading a very fine line’, de Bretton-Gordon said of its use in Mosul.
‘[ISIS] snipers are high up in buildings and are picking off coalition fighters. [ISIS is] also using chlorine and mustard agent (gas) to force troops into gas masks or force them to disperse if they don’t have gas masks.
‘Morally it is slightly more difficult as we know. [ISIS is] using civilians as human shields’.
De Bretton-Gordon noted that these decisions are difficult. Coalition commanders are rationing air strikes after an outcry over the level of civilian casualties.
The danger lies less in the fight against ISIS and more in the judgment of history. White phosphorus use is associated with chemical war crimes. If it is used at all, it must be used carefully, lest coalition and partner forces suffer the same association.
This piece was originally published in The Arab Weekly.