Which country did the US invade in 2003 because it believed that the country possessed weapons of mass destruction?

In 2003, the United States invaded Iraq based on the belief that the country possessed weapons of mass destruction (WMDs). This military action was justified by the U.S. government under the premise that Iraq posed a threat to international security. However, subsequent investigations found no WMDs in Iraq, leading to widespread criticism of the invasion and its justification.