In 1990 Saddam ordered his army to invade Kuwait and seize power. The U.S. and UN saw this as a violation of Kuwait’s sovereignty. In 1991, after a brief UN approval process, the U.S. and its coalition sprang into action. After a short engagement, they successfully stopped the Iraqi army and pushed them back across the border into Iraq. This conflict was known as the Gulf War.

During and after the war, Arabs had admired Saddam as a leader who dared to defy and challenge western powers. This admiration would loosely united the Arab world in the stance Saddam took. Saddam was a Sunni Muslim ruling in a predominantly Shia Iraq. Although his party was greatly outnumbered, against all the odds, Saddam’s ruthless policies and behavior were said to keep a balance of peace between the two Islamic sects in the country.

Following the war, and the exposure of the weak Iraqi army, the empowered Shiites in southern Iraq started a rebellion against Saddam. After the embarrassingly quick defeat at the hands of the U.S. coalition, Saddam desperately wanted to regain his stature among the people of Iraq by any means necessary. He struck down hard on the rebellion in his typical murderous fashion, slaughtering thousands of Shiites suspected — or not — of opposing him. It was at this point that allegations of the use of chemical and biological weapons against his people started surfacing.

As a result, the UN placed economic sanctions on Iraq.

Most would argue that the 2001 al-Qaida attacks on the U.S. triggered the U.S. to oust Saddam from power once and for all — a job most would agree should have been accomplished during the Gulf War.

Here are the fundamental reasons that ultimately led to the 2003 U.S. invasion of Iraq.

The Ba’ath Party, Saddam Hussein's vehicle to power

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9/11 and the 1991 Gulf War were key influences that put Saddam in the world’s crosshairs.

The Bush administration called it a “belated reckoning” that needed to happen. Up to this point, Saddam had invaded or attacked four neighboring countries in the recent past and was directly responsible for the deaths of tens of thousands of Iraqi people. Also, post-Gulf War, a defeated Saddam had resorted to the mass slaughter of Kurds and Shiites. Many of the leaders in D.C. wanted to right the mistake of having left Saddam in power. But the issue was all but forgotten until 9/11 brought a crashing reminder of the Iraq-based al-Qaida terrorism.

The threat of Weapons of Mass Destruction in the hands of a “mad man” fueled the cause of the U.S. even further.

With the prospect of WMDs in Iraq, and given the unpredictability of Saddam’s actions, the CIA claimed that the intelligence of the overall situation was a “slam dunk.” Eastern governments, as well as a collection of European intelligence agencies, backed the U.S. intelligence. Of course, as we know now, Iraq never fully developed WMDs. This would later become a “critical political mistake.”

The rapid victory in Afghanistan was another reason for the invasion of Iraq. An eight-week war in Afghanistan had led to the removal of the Taliban who were controlling the country. The prospect of nation-building in Afghanistan was not appealing to the U.S. considering Afghanistan’s reputation as the “graveyard of empires.” Shortly thereafter, the emplacement of pro-western president Hamid Karzai had also given the U.S. a political power they could trust.

Karzai wanted the U.S. to focus its attention elsewhere. He “misled the Bush administration into thinking Iraq would be a far less challenging prospect — especially given Iraq’s humiliating defeat in 1991, which had contrasted sharply with the Soviet Failure in Afghanistan.”

There was also bipartisan support from Congress, the media, and the public in the U.S. The removal of Saddam, at this point, was a priority for more reasons than just 9/11 and the potential existence of WMDs. The instability and “genocide against the Kurds, Shiites, and Marsh Arabs; bounties for suicide bombers; a sanctuary for terrorists; attempts to kill a former U.S. president; violations of U.N. sanctions and resolutions” were a laundry list of reasons the bipartisan support was so strong.

The idea was that instead of Iraq being the problem in the Middle East, it could potentially become a solution. But stability between religious sects and a bipartisan democratic government, which would balance the power in the country, was a necessity for that. Such a government, by its existence, would pressure the Gulf monarchies to liberalize and cease their support for terrorism of the sort that had killed 3,000 Americans. And from a purely strategic standpoint, in contrast to Afghanistan, Iraq had ports, good weather, flat terrain, a far more literate populace, and oil, making its prospects of long-stability better.

Oil was among the most controversial reasons for the invasion; but the issue was misinterpreted. The simple fact is “the war was not a matter of blood for oil.” The U.S. government had no intention of taking Iraqi oil, “a fact proven by the transparent and non-U.S. postwar development of the Iraqi oil and gas fields.” The fundamental issue of oil in Iraq stems from the fact that Iraq’s oil revenues were the source of Saddam’s funding. Because of the oil, “Saddam would always have the resources to stimulate trouble in the region, would always be difficult to remove through internal opposition, and would always use petrodollar influence to undermine UN resolutions, seek to spike world oil prices, or distort Western solidarity.”

The U.S. invasion of Iraq began in 2003. It defeated his army and cleaned out his regime in a matter of months. In the 2005 Iraqi elections a Shia political parties came to power in the country.

This was a huge turning point for Iraq. Consequently, the sectarian violence between Sunni and Shia Muslims intensified. As a result of the invasion and the political change of power, an insurgency erupted, led by Sunni Ba’athists and al-Qaida. The Sunnis fear being ruled by Shiite leadership. This prompted them to retaliate against the new democratic regime and continue to sabotage the prospects of peace.

On the evening of December 13, 2003, in the small Iraqi town of ad-Dawr outside of Tikrit, elements of Task Force 121, and the US Army’s 4th Infantry Division captured former Iraqi dictator Saddam Hussein. Hussein was hidding in a spider hole and was found by a Delta Force operator.