Operation Iraqi Freedom: The Biggest Consequence of the American Invasion of Iraq

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     In 2003, the United States invaded Iraq on the pretext of Iraq possessing weapons of mass destruction (WMD).  According to a radio address by former president George W. Bush, "Our cause is just, the security of the nations we serve and the peace of the world. And our mission is clear, to disarm Iraq of weapons of mass destruction, to end Saddam Hussein's support for terrorism, and to free the Iraqi people."

U.S. Solider perparees to take
the statue of Saddam Hussein.
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 What was estimated at first to be a very short and straight forward operation turned out to be a long and grueling process. Once the regime of Saddam Hussein was brought down (literally and symbolically), there was no state infrastructure left to hold Iraqi society together.

The Iraqi citizens, under threat, began to form militias to protect their own people. Iran had long wanted to see the fall of Saddam Hussein-- during the Iran-- Iraq war Ayatollah Khomeini originally refused to stop fighting until Hussein was removed from power. With Hussein out of the way, Iran was free to exert its influence on Iraq's Shi'a majority.
As a consequence of Iran exerting influence on the Shi'ites in Iraq and militias protecting their own sectarian violence skyrocketed. A series of maps shows the change of Baghdad over a few years from a largely mixed city to a predominantly Shi'a city:

The maps are color coded to show majority populations from 2003[top left], 2006 [top right], 2007[bottom left], and 2008 [bottom right].
Green= Shi'a Majority   Red= Sunni Majority  Blue= Christian Majority and Orange= Mixed
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A Sunni newspaper published the following political cartoon: Translations and image provided by BBC Middle East

"The cartoon depicts the map of Iraq as a pool of fuel leaked from a barrel with an Arabic phrase reading "Maliki's sectarianism" written on it. Then, a hand holding a lit torch seems to be trying to set fire to Iraq. On the sleeve, the word Iran is written, while the torch bears the name of the Iranian "al-Quds brigade".

Other evidence of rising sectarianism after the fall of Saddam Hussein includes the emergence of Sunni extremist group Da'ish (ISIS/ISIL/IS). Da'ish has been able to control a significant portion of Iraqi terrority. This would not have been possible before the U.S. invasion of Iraq.

Source: BBC

The Yazidis- Who Are They and Why Are They in Today's News?

BBC News: Who are the Yazidis in 60 Seconds

The Yazidis are a religious minority in Iraq. Though they have faced persecution throughout their history, currently they suffer at the hands of Da'ish and make an appearance in western media outlets.

Source: BBC News 

Roughly 40,000 Iraqis belonging to minority groups (mostly Yazidi) were forced to flee Da'ish to Mt. Sinjar in 2014. Here there is a severe lack of food and water. If the refugees leave the mountain for more resources, they risk violent death from members of Da'ish. There have been many pleas for humanitarian aid including one from a member of Iraqi parliment, Fiyan Dakheel, who tearfully pled, “We are being butchered under the banner of there is no God but God,”
The U.S. has provided humanitarian aid to those trapped on Mt. Sinjar but has no current plans for evacuation.

In October 2014 U.N. Assistant Secretary-General for Human Rights Ivan Simonovic stated during an interview that ,"Facts are indicating that [Da'ish] actions against Yazidis may amount to attempted genocide." 

According to  an article in American Aljazeera the majority of those who have not fled the area have been shot, buried alive, sold into slavery, forced to convert, imprisoned and or sexually assaulted.