In 1980 the UN Convention on Conventional Weapons banned the use of such weapons against civilian targets. The US did not sign that treaty.
I expect this will be updated to Project Censored's account from its 2006 #2 story Media Coverage Fails on Iraq: Fallujah and Civilian Deathtoll. I still hold out hope that it isn't true, but if the media never digs into the story how will anyone ever know either way for certain?
EDIT: Here are two skeptical questions I would have for the film makers.
- If white phosphorous can burn through to the bone, why did the corpses still have clothing?
- Several of the corpses were covered in maggots and looked to be in advanced stages of decomposition, what distinguishes these corpses from corpses burned from white phosphorous or MK 77?
Update - It doesn't help that the US military denied using white phosphorous for anything more than illumination purposes, since as seen at the Daily Kos entry linked above, that is not true, as the March edition of the army publication of Field Artillery Magazine writes
WP [i.e., white phosphorus rounds] 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 when we could not get effects on them with HE. We fired 'shake and bake' missions at the insurgents, using WP to flush them out and HE to take them out.Americablog points out that the government response to these allegations had been
Phosphorus shells are not outlawed. U.S. forces have used them very sparingly in Fallujah, for illumination purposes. They were fired into the air to illuminate enemy positions at night, not at enemy fighters.*This is an error on my part for using the first figure I saw without checking other sources, especially given the source I used for the 50,000 figure was Project Censored. I've since seen sources estimate that the civilians in Fallujah numbered as low as 5,000 at the time of attack, most notably by Middle East expert Juan Cole, so the number is likely somewhere in between those two estimates.