The United States is at war again in Iraq — for the third time in 25 years. Our main enemy this time is not Saddam Hussein or Al-Qaeda, but the Islamic State in Iraq and Syria (ISIS), sometimes called the Islamic State of Iraq and the Levant (ISIL). Composed largely of militants claiming a strict adherence to Islamic law as interpreted within the Sunni branch of that religion, ISIS has seized the heartland of Iraq and much of eastern Syria. ISIS’ followers have massacred thousands of Muslim and Christian civilians who oppose their rule. Most startling to Americans, ISIS leaders have beheaded two U.S. journalists on video, trumpeting the brutality of the regime to the world. They have beheaded many others, and they promise more of the same in coming weeks.

The threat to the United States and its allies is clear. ISIS is growing as it draws recruits from around the Middle East as well as Europe, Australia and even our own country. Like the Taliban in Afghanistan before 2001, ISIS has formed a state of its own that it is using to train terrorists.  ISIS controls oil and other resources that finance its expanding operations. This is an organization that has the will and the capability to spread violence far beyond its borders. Whether ISIS can attack the territory of the United States is debatable, but its capacity for warfare in the greater Middle East and terrorism in parts of Europe and Asia is widely accepted. The British government has already raised its national terror level to “severe” in anticipation of imminent attacks from ISIS-inspired militants.

This global terrorist threat from ISIS is real, but it raises many questions about how the United States should respond. Another full-scale war, with ground troops deployed in large numbers to the Middle East, is neither acceptable to American citizens nor favorable to American strategic interests. The United States confronts a range of pressing challenges in other areas, especially Ukraine, and it cannot divert its overstretched military forces in Iraq again.

More significant, the evidence is overwhelming that previous American military activities in the Middle East contributed to the current threat. The United States created a political vacuum by overthrowing the dictatorship of Saddam Hussein in Iraq without an alternative. Washington subsequently supported a sectarian Shiite-led government that alienated Sunni citizens, many of whom now support ISIS. The United States then withdrew most of its military capabilities from the country, leaving behind near-civil war conditions.

Many of the extremists in ISIS today, including its leader, Abu Bakr al-Baghdadi, spent the period of American occupation in prisons operated by the U.S. Army. They were radicalized by the combined experiences of dictatorship, war and occupation. They view both the long-standing rulers in the region and the American occupiers as oppressors. They have turned to Islam in its most extreme and pure form as an alternative. They are also using Islam as a justification for seizing power and killing thousands of innocent people.

This history is crucial for present policy because it should caution Americans against assuming that overwhelming force will solve the current problem. U.S. military power can help defeat ISIS, but it must be matched with effective political change on the ground. This involves supporting local actors like the Kurdish leaders, who are committed to building functional, participatory and inclusive institutions. Effective policy also requires a long-term commitment to a process of compromise between local groups rather than favoritism for one or two. The United States must develop the regional expertise, nurture the contacts on the ground and work with other international actors (including the United Nations) to support a process of governance among groups now at war. American air strikes and other military actions will only work if they are part of a multilateral strategy including diverse Iraqi, Syrian and, yes, Iranian figures who oppose ISIS.

The terrors perpetrated by ISIS are truly horrific and threatening. For moral and security reasons we must stop them. We cannot, however, do it alone, and we cannot do it from a distance. A new generation of policy-makers — including current students — must learn that American force contributes to international peace only when accompanied by extensive cooperation with diverse local actors, many of whom we might not like. Despite all of our idealistic rhetoric, international politics is fundamentally about working with the mix of local groups to exclude the worst elements. Until we do that, we will never escape the cycle of recurring war.  

Suri is a professor in the LBJ School of Public Affairs and the department of history.