Congress passed its joint resolution in October 2002, authorizing the president to use military force against Saddam Hussein's regime.[33] However, The Iraq Intelligence Commission confirmed in its 2005 report that no nuclear weapons or biological weapons capability existed. Many critics questioned the true intention of Bush administration for invading Iraq, based on possibility of retaliation on the terrorist attacks which occurred on September 11, 2001. It is still unclear whether the U.S. invasion of Iraq was legally justifiable and, what, if any, gains were achieved by the U.S. as a result of the war. [citation needed]