As the risk of a war between the US and Iran increases, concerns are high about the potential consequences of such a conflict for Iraq. In early May, US Secretary of State Mike Pompeo visited Baghdad and expressed concerns to Iraqi officials that Iran-backed militias might launch rocket attacks on US forces there. The US pulled non-emergency personnel out of its Baghdad Embassy. In June, two rockets landed near a compound associated with US company ExxonMobil, and there were a couple of small-scale rocket attacks on US military units. While limited so far, these events have highlighted the risks in Iraq. The exact consequences for Iraq would depend on how a US-Iran war played out. The most likely scenarios do not envision a full-scale US invasion of Iran with ground forces. Rather, likely scenarios range from a limited number of small attacks to a wide-ranging conflict involving naval battles, air strikes on Iran, Iranian missile attacks on regional targets, and proxy warfare. Regardless of how a war actually plays out, it is almost certain to affect Iraq. As a neighboring country to Iran, in which both Iran and the US have significant influence and interests, any conflict is very likely to include Iraq. Iran’s reliance on asymmetric warfare to balance against the US’ far greater military power is another factor that ensures a war would affect Iraq. Direct fighting between Iranian and US forces on Iraqi territory is a possibility. The US reportedly has about 5,200 soldiers in Iraq today, and Iran very likely has Islamic Revolutionary Guard Corps or other forces on the ground. Direct Iranian missile strikes on US bases in Iraq could occur. The bigger concern is the potential role of Iraqi militias with a pro-Iran orientation and which often receive direct support from Tehran. The potential role of these militias is complicated. Each has its own interests and varying degrees of fealty to Iran. Some see themselves as loyal to Iran, while others see it as a convenient partner but their loyalty is to Iraq or their own communities. In some cases, leaders with different views on this issue work together within the same militia. Iran has very significant influence over militias such as Kata’ib Hezbollah, Harakat Al-Nujaba and Asaib Ahl Al-Haq, but it does not have total control over many of the militias it supports. Nonetheless, there is little question that these militias are far friendlier toward Iran than the US and would likely side with Tehran in a war. The Iraqi government must balance its need for US support with the reality of Iranian influence. Kerry Boyd Anderson Other complications surround the militias’ role in government and in fighting Daesh. Most of them are part of the Popular Mobilization Forces (PMF), in which they serve as part of the Iraqi armed forces, but they also have their own interests. Many of them fought against Daesh. The Iraqi government is working to professionalize the PMF and address the reality that the government needs the militias, but also wants more control over them. However, the militias have their own sources of funding and arms, with loyalty to community leaders and militia commanders rather than to the government in Baghdad. Those who ally with Iran in a US-Iran war could quickly become threats to US forces and interests in Iraq. Politically, Prime Minister Adil Abdul-Mahdi leads a fragile coalition, while Iraq continues to struggle to stabilize following its long war and the campaign against Daesh. The relative political stability that has been in place since the 2018 elections might not survive the pressures of a US-Iran war, especially as the PM has rivals who might exploit an increasingly challenging environment. The Iraqi government must balance its need for US support with the reality of Iranian influence — a difficult balancing act at the best of times and one that could bring down the government in a war. There are also economic concerns for Iraq. A naval conflict in the Arabian Gulf could affect Iraq’s oil exports. Iran also has various forms of economic leverage over Iraq, notably through electricity supplies, which it could use to pressure the government to take its side. However, Iran strongly benefits from those economic ties and might be reluctant to push economic retaliation against Baghdad too far. The biggest fear is that a US-Iran war might destabilize Iraq, pushing it back into instability and violence. This could start with pro-Iran militias attacking US forces, demonstrating the lack of Iraqi government control and leading to US counterattacks. In a country that has previously been torn apart by sectarian and communal violence and has barely reclaimed a degree of peace, it might not take much to push the country back into civil war. Instability in Iraq might also create opportunities for Daesh to re-emerge and coalesce as a fighting force, particularly if US forces and Shiite militias are engaged in fighting each other and if Kurdish Peshmerga forces are focused on protecting the Kurdistan Region of Iraq from Iran. As tensions between Washington and Tehran increase, neither country fully controls the situation in Iraq. Both have allies, but there are many individuals, such as Muqtada Al-Sadr, and groups that pursue their own interests. Conflict in Iraq gets messy. Regardless of one’s views on a US-Iran war, those who want a stable Iraq that is independent of Iran should think through the consequences of a war for Iraq and be prepared to offer it significant support to endure a regional conflict.