US used chemical weapons in Iraq, then lied

George Monbiot: US used chemical weapons in Iraq, then lied: 
"The first account they unearthed in a magazine published by the US army. In the March 2005 edition of Field Artillery, officers from the 2nd Infantry's fire support element boast about their role in the attack on Falluja in November last year: "White Phosphorous. 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 when 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."