Maybe this will help you understand...

During his period as Reagan's Special Envoy to the Middle East, Rumsfeld was the main conduit for crucial American military intelligence, hardware and strategic advice to Saddam Hussein, then fighting Iran in the Iran-Iraq war. During this period, US policy supported Iraq, believing it to be a useful buffer against Iran's new religious government. When he visited on December 19-20, 1983, he and Saddam Hussein had a 90 minute dicussion which covered Syria's occupation of Lebanon, preventing Syrian and Iranian expansion, preventing arms sales to Iran by foreign countries, increasing Iraqi oil production via a possible new oil pipeline across Jordan. Not mentioned was Iraqi production and use of chemical weapons. The Iranian government had cited several Iraqi air and ground chemical weapons attacks in the previous two months, and the Iranian news agency had reported the use of chemical weapons as early as 1981. The US State Department first condemned the use of chemical weapons in the war on March 5, 1984, two days before the ICRC confirmed Iranian allegations.

Donald Rumsfeld