The U.S. and Iraq have gone to war twice in 30 years. The second time, American invaders deposed an oppressive regime led by strong-man Saddam Hussein. In the process, they unleashed long-suppressed sectarian divisions within Iraq and stoked the rise of Islamic State. In recent years, Iraqi officials worked closely with the Americans to try to establish stability and security in Iraq, even as Iraq also aligned with neighboring Iran, America’s foe. After the U.S. assassinated a top Iranian general in Iraq on Jan. 2, the country’s leaders reconsidered the relationship anew.

1. What’s the current relationship based on?

The U.S. has about 5,000 troops in Iraq to prevent a resurgence of the defeated fighters of Islamic State. The American presence serves to counterbalance Iran’s powerful influence in the country, which it exerts through allied Iraqi politicians and militias. The U.S. also aims to prevent a splintering of Iraq, which is made up of a Shiite Muslim majority that dominates the south, Sunni Muslims who prevail in the country’s center, and Kurds who live mostly in the northeast. U.S. officials worry that Iraq’s division along sectarian lines could fuel other conflicts in the Middle East. For its part, Iraq looks to the U.S. for much-needed assistance to rebuild its military, train its police force and provide the stability necessary for reconstruction after decades of war and economic mismanagement.

2. What are the connections?

Only Afghanistan receives more foreign assistance annually from the U.S. than Iraq. U.S. lawmakers have appropriated more than $5.8 billion since 2014 to train and equip Iraqi forces. In the same period, the U.S. has provided $2.5 billion in humanitarian aid. It’s spent $365 million supporting recovery efforts in areas liberated from Islamic State. In addition to supporting Iraqi operations against the militants, the U.S. leads a coalition combating Islamic State that engages more than 70 nations. A legacy of the U.S. occupation of Iraq after its 2003 invasion, the 104-acre U.S. Embassy compound in Baghdad is the biggest in the world. It cost more than $700 million to build, housed 16,000 people at its peak, and has its own power stations and water facilities.

3. Why did the U.S. first go to war with Iraq?

After Iraq’s independence in 1932, the two countries had checkered relations, with Iraq swinging from the American to the Soviet sphere during the Cold War. That didn’t stop the U.S. from supplying Iraq with logistical and intelligence assistance during its bloody war with Iran from 1980-1988; the U.S. worried that Iran would succeed in its goal of exporting the Islamic fundamentalism behind its 1979 revolution. Then, in 1990, Saddam Hussein’s regime invaded neighboring oil-rich Kuwait and announced its annexation to Iraq. Under President George H.W. Bush, the U.S. built a coalition of forces that ejected Iraqi forces from Kuwait the following year. At that time, American officials ruled out sending forces to Baghdad to topple Saddam’s regime out of concern it would entangle the U.S. in Iraq.

4. What led to the second war?

After the Sept. 11, 2001, terrorist attacks on the U.S. by the Afghanistan-based jihadist group al-Qaeda, the U.S., under President George W. Bush, George H.W. Bush’s son, accused the Iraqi regime of having links with al-Qaeda and of continuing to possess weapons of mass destruction, some of which had been discovered and destroyed by United Nations inspectors after the 1991 war. In 2003, the U.S. invaded Iraq and dismantled Saddam’s regime. It never proved the link to al-Qaeda or found any additional weapons of mass destruction.

5. What were the consequences of the invasion?

Ending Saddam’s regime, which had been dominated by Sunnis, facilitated the emergence of a government led by Shiites, many of whom have close ties to majority-Shiite Iran. Disaffection among Iraqi Sunnis, resulting from their loss of power as well as the U.S. occupation, fed the rise of the radical Sunni group al-Qaeda in Iraq, the predecessor to Islamic State. The group surged after the U.S. withdrew from Iraq in 2011 following a failure by the two governments to agree on terms for a continued stay. Islamic State honed its combat skills in the Syrian civil war that began the same year. In 2014, it began conquering Iraqi and Syrian cities and declared a caliphate, a state that claims dominion over Muslims. Taking advantage of the chaos, Iraq’s semi-autonomous Kurdistan Regional Government seized territory in and around the oil-rich city of Kirkuk and in 2017 held a referendum endorsing independence. The national government dismissed the vote and dispatched troops to retake Kirkuk.

6. When did U.S. forces return to Iraq?

They returned in 2014 at the invitation of Iraq’s government after its army collapsed under the advance of Islamic State. The U.S.-led coalition combined airstrikes with support for local forces fighting the group on the ground. Islamic State was pushed from its last urban stronghold in Iraq in mid-2017 and in Syria at the end of 2018. Its surviving fighters have turned to insurgency tactics such as bombings, sniper attacks and targeted killings in both countries. In its campaign against the group, Iraq’s government has leaned heavily not just on the U.S.-led coalition but on Shiite militias, some of which are backed by Iran. The U.S. blamed one such militia for a December rocket attack on an Iraqi base housing American personnel and a siege of the U.S. Embassy in Iraq, acts that precipitated the U.S. killing of Iranian General Qassem Soleimani in a drone strike near the Baghdad airport.

7. How did Iraq respond?

In response to Soleimani’s killing, Iraq’s parliament voted in a non-binding resolution to require the government to “end any foreign presence on Iraqi soil and prevent the use of Iraqi airspace, soil and water for any reason” by foreign troops. Caretaker Prime Minister Adel Abdul Mahdi indicated he will act on the legislation, but its unclear exactly what the consequences for U.S. personnel would be. A dis-invitation to U.S. troops might still allow for trainers to continue working with the Iraqi armed forces, and for U.S. jets to fly counter-Islamic State operations from the Kurdish region. In a tweet, Trump threatened to impose sweeping sanctions on Iraq should it kick out American troops without compensation, while U.S. Secretary of Defense Mark Esper said no decision had been made to pull troops from the country.

To contact the reporter on this story: Glen Carey in Washington at gcarey8@bloomberg.net

To contact the editors responsible for this story: Bill Faries at wfaries@bloomberg.net, Lisa Beyer

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