Newly declassified CIA documents "combined with exclusive interviews with former intelligence officials, reveal new details about the depth of the United States' knowledge of how and when Iraq" used chemical weapons against Iran in the 1980s, Foreign Policy reports.

According to the magazine:

"In 1988, during the waning days of Iraq's war with Iran, the United States learned through satellite imagery that Iran was about to gain a major strategic advantage by exploiting a hole in Iraqi defenses. U.S. intelligence officials conveyed the location of the Iranian troops to Iraq."

For several years before that, CIA documents show, U.S. officials were aware that Iraq had been using chemical weapons in its long war against neighboring Iran and likely would again.

That's just what happened, according to Foreign Policy:

"The Iraqis used mustard gas and sarin prior to four major offensives in early 1988 that relied on U.S. satellite imagery, maps, and other intelligence. These attacks helped to tilt the war in Iraq's favor and bring Iran to the negotiating table, and they ensured that the Reagan administration's long-standing policy of securing an Iraqi victory would succeed."

The new report comes, of course, as the U.S. and other nations weigh whether to use military force to send a message to Syrian President Bashar Assad following last week's alleged chemical weapons attack on civilians near Damascus.

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