Hostilities of the Gulf War were suspended on 28 February 1991, with a cease-fire negotiated between the UN Coalition and Iraq.
The U.S. and its allies tried to keep Saddam in check with military actions such as Operation Southern Watch, which was conducted by Joint Task Force Southwest Asia (JTF-SWA) with the mission of monitoring and controlling airspace south of the 32nd Parallel (extended to the 33rd Parallel in 1996) as well as using economic sanctions.
It was revealed that a biological weapons (BW) program in Iraq had begun in the early 1980s with help from the U.S. and Europe in violation of the Biological Weapons Convention (BWC) of 1972.
Details of the BW program—along with a chemical weapons program—surfaced after the Gulf War (1990–91) following investigations conducted by the United Nations Special Commission (UNSCOM) which had been charged with the post-war disarmament of Saddam's Iraq.
The investigation concluded that the program had not continued after the war.
The U.S. and its allies then maintained a policy of "containment" towards Iraq.
This policy involved numerous economic sanctions by the UN Security Council; the enforcement of Iraqi no-fly zones declared by the U.S. and the UK to protect the Kurds in Iraqi Kurdistan and Shias in the south from aerial attacks by the Iraqi government; and ongoing inspections.
Iraqi military helicopters and planes regularly contested the no-fly zones.

In October 1998, removing the Iraqi government became official U.S. foreign policy with enactment of the Iraq Liberation Act.
Enacted following the expulsion of UN weapons inspectors the preceding August (after some had been accused of spying for the U.S.), the act provided $97 million for Iraqi "democratic opposition organizations" to "establish a program to support a transition to democracy in Iraq."
This legislation contrasted with the terms set out in United Nations Security Council Resolution 687, which focused on weapons and weapons programs and made no mention of regime change.
One month after the passage of the Iraq Liberation Act, the U.S. and UK launched a bombardment campaign of Iraq called Operation Desert Fox.
The campaign's express rationale was to hamper Saddam Hussein's government's ability to produce chemical, biological, and nuclear weapons, but U.S. intelligence personnel also hoped it would help weaken Saddam's grip on power.

With the election of George W. Bush as president in 2000, the U.S. moved towards a more aggressive policy toward Iraq.
The Republican Party's campaign platform in the 2000 election called for "full implementation" of the Iraq Liberation Act as "a starting point" in a plan to "remove" Saddam.
After leaving the George W. Bush administration, Treasury Secretary Paul O'Neill said that an attack on Iraq had been planned since Bush's inauguration and that the first United States National Security Council meeting involved discussion of an invasion.
O'Neill later backtracked, saying that these discussions were part of a continuation of foreign policy first put into place by the Clinton administration.

Despite the Bush administration's stated interest in invading Iraq, little formal movement towards an invasion occurred until the 11 September attacks.
For example, the administration prepared Operation Desert Badger to respond aggressively if any Air Force pilot was shot down while flying over Iraq, but this did not happen.
Secretary of Defense Donald Rumsfeld dismissed National Security Agency (NSA) intercept data available by midday of the 11th that pointed to al-Qaeda's culpability, and by mid-afternoon ordered the Pentagon to prepare plans for attacking Iraq.
According to aides who were with him in the National Military Command Center on that day, Rumsfeld asked for: "best info fast.
Judge whether good enough hit Saddam Hussein at same time.
Not only Osama bin Laden."
A memo written by Rumsfeld in November 2001 considers an Iraq war.
The rationale for invading Iraq as a response to 9/11 has been widely questioned, as there was no cooperation between Saddam Hussein and al-Qaeda.

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Hostilities of the Gulf War were suspended on 28 February 1991, with a cease-fire negotiated between the UN Coalition and Iraq. The U.S. and its allies tried to keep Saddam in check with military actions such as Operation Southern Watch, which was conducted by Joint Task Force Southwest Asia (JTF-SWA) with the mission of monitoring and controlling airspace south of the 32nd Parallel (extended to the 33rd Parallel in 1996) as well as using economic sanctions. It was revealed that a biological weapons (BW) program in Iraq had begun in the early 1980s with help from the U.S. and Europe in violation of the Biological Weapons Convention (BWC) of 1972. Details of the BW program—along with a chemical weapons program—surfaced after the Gulf War (1990–91) following investigations conducted by the United Nations Special Commission (UNSCOM) which had been charged with the post-war disarmament of Saddam's Iraq. The investigation concluded that the program had not continued after the war. The U.S. and its allies then maintained a policy of "containment" towards Iraq. This policy involved numerous economic sanctions by the UN Security Council; the enforcement of Iraqi no-fly zones declared by the U.S. and the UK to protect the Kurds in Iraqi Kurdistan and Shias in the south from aerial attacks by the Iraqi government; and ongoing inspections. Iraqi military helicopters and planes regularly contested the no-fly zones.
In October 1998, removing the Iraqi government became official U.S. foreign policy with enactment of the Iraq Liberation Act. Enacted following the expulsion of UN weapons inspectors the preceding August (after some had been accused of spying for the U.S.), the act provided $97 million for Iraqi "democratic opposition organizations" to "establish a program to support a transition to democracy in Iraq." This legislation contrasted with the terms set out in United Nations Security Council Resolution 687, which focused on weapons and weapons programs and made no mention of regime change. One month after the passage of the Iraq Liberation Act, the U.S. and UK launched a bombardment campaign of Iraq called Operation Desert Fox. The campaign's express rationale was to hamper Saddam Hussein's government's ability to produce chemical, biological, and nuclear weapons, but U.S. intelligence personnel also hoped it would help weaken Saddam's grip on power.
With the election of George W. Bush as president in 2000, the U.S. moved towards a more aggressive policy toward Iraq. The Republican Party's campaign platform in the 2000 election called for "full implementation" of the Iraq Liberation Act as "a starting point" in a plan to "remove" Saddam. After leaving the George W. Bush administration, Treasury Secretary Paul O'Neill said that an attack on Iraq had been planned since Bush's inauguration and that the first United States National Security Council meeting involved discussion of an invasion. O'Neill later backtracked, saying that these discussions were part of a continuation of foreign policy first put into place by the Clinton administration.
Despite the Bush administration's stated interest in invading Iraq, little formal movement towards an invasion occurred until the 11 September attacks. For example, the administration prepared Operation Desert Badger to respond aggressively if any Air Force pilot was shot down while flying over Iraq, but this did not happen. Secretary of Defense Donald Rumsfeld dismissed National Security Agency (NSA) intercept data available by midday of the 11th that pointed to al-Qaeda's culpability, and by mid-afternoon ordered the Pentagon to prepare plans for attacking Iraq. According to aides who were with him in the National Military Command Center on that day, Rumsfeld asked for: "best info fast. Judge whether good enough hit Saddam Hussein at same time. Not only Osama bin Laden." A memo written by Rumsfeld in November 2001 considers an Iraq war. The rationale for invading Iraq as a response to 9/11 has been widely questioned, as there was no cooperation between Saddam Hussein and al-Qaeda.
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2003 invasion of Iraq