The article examines the level of awareness of US officials regarding the Iraqi program for the production of chemical weapons as well as its use before 1988. Both in Russian and foreign historiography, the issue of Iraq's chemical weapons and the United States relationship with the government of Saddam Hussein during the Iran-Iraq war is either considered superficially or becomes only an aspect of more general and extensive research topics. The period of 1980-1988 was marked by active USA-Iraqi cooperation in order to exert pressure on Iran. It is proved that during this period, Washington was fully aware of the development and use of chemical weapons by Iraq from the first incidents, even before the issue was brought to the level of the UN Security Council. It was not profitable for the United States to promote the dissemination of information discrediting an ally in the fight against Iran. World`s attention to the use of chemical weapons was drawn only after the end of the Iran-Iraq war.