As the presidential campaigns launch into full swing, there is little doubt that debating the effectiveness of U.S. efforts to combat ISIS will take center stage. Critics of the current administration’s policy have argued that the strategy of containment to “degrade and destroy” ISIS has been ineffective. This camp asserts that ISIS is a long way from being destroyed and is not even being contained: ISIS has expanded its reach to other territories, increased its attacks on targets outside its borders, and its ideological appeal shows no sign of decline. Meanwhile, supporters of the current approach remind us that this will be a long war and also point out that Islamic State has lost significant territory, its finances are being depleted, its recruitment is down, and local counter-ISIS forces are getting stronger.

Yet both views miss the mark about a crucial aspect of U.S. policy: containment. Cultivated in the early days of the Cold War to prevent the expanding influence of the Soviet Union, a massive state with a strong ideology and robust military, George Kennan’s interpretation of containment highlights its limitations within the context of ISIS. Containment cannot be applied the same way it was against ISIS, an elusive adversary that has the characteristics of a state, a transnational terrorist organization and a social movement. Moreover, it is much harder to contain an ideological threat than a military one, as the U.S. experience with the Soviet Union showed. It is essential that policy makers recognize what containment can and can’t do against ISIS.

Instead, containment should be understood as a way to limit ISIS’s territorial expansion in Iraq and Syria, and not as an effort to destroy the organization. This is a tall order during a highly charged election season, where the policy alternatives range from carpet bombing to committing large numbers of troops. Thus, to move the counter-ISIS efforts into the win column, the United States should set three realistic expectations. First, it should make clear that the United States can contain ISIS as a state or an insurgent group, but it cannot contain its ideology. Second, the United States can prevent ISIS’s expansion in the peripheral areas by bolstering communal resilience to contain its transnational affiliates. Third, the United States should continue to bolster our defenses against attacks on U.S. soil.

What Is Containment?

Defined as restricting the activities of an actor to a demarcated territory, containment has been the cornerstone of the administration’s strategy to eventually defeat and eliminate ISIS. The logic that undergirds this effort is that it avoids a large scale and costly military intervention that could cause more harm than good.

Understanding the history of containment can provide insights for how to develop a more effective and realistic assessment of counterterrorism strategy. The containment doctrine was developed by George Kennan, a diplomat and director of the Policy Planning Staff for President Truman, to prevent Soviet expansion while limiting American military commitments in the aftermath of World War II. Kennan’s famous “Long Telegram,” a cable sent from Moscow to the State Department in 1946, suggested a strategy toward the Soviet Union that recognized the limits of containment. Kennan believed that containment policy should focus on limiting Soviet expansionism through non-provocative resistance while waiting for internal implosion. This approach predated the push for “rollback” that became a part of foreign policy thinking in the 1950s and 1960s.

With the continued airstrikes and financial strangulation, the hope is that ISIS, which has developed governing institutions, will ultimately implode from within, similar to the way the Soviet Union did. In fact, containment counsels patience and reminds us that the Cold War against the Soviets lasted decades. Others who believe it has the characteristics of a state argue that Islamic State will likely follow the path of many other revolutionary states and be socialized within the international system.

Kennan’s specific understanding of containment as a means by which to deal with the threat posed by territorial expansion of the Soviet Union reveals the limitations and possibilities of existing U.S. counterterrorism policies. While a policy of containing ISIS has reduced its territorial expansion in Iraq and Syria, containment is not a path to complete defeat. In order to develop more effective counterterrorism policies, it is necessary to understand what ISIS is. So while containment is an appropriate strategy against ISIS as a statelike entity with control over territory, it is not appropriate for addressing the threat posed by ISIS as a social movement or a transnational territory organization.

What Is ISIS?

After ISIS’s brazen attacks in Paris in November 2015, critics of the administration were quick to point out that ISIS was not contained, as the president had claimed. The administration was right to claim that this referred to a specific territory. But through this debate, both the president and his critics were assessing the effectiveness of containment, without an agreement on whether containment meant preventing the geographic expansion of ISIS’s state, the ideological spread of the organization, or both. Identifying that ISIS poses a threat as a state, insurgent group, ideological movement and transnational terrorist organization is necessary to evaluate current policy and formulate future policy.

First and foremost, ISIS can be seen as a state or an insurgent group that exercises territorial and political control in both Syria and Iraq. The Obama administration’s military strategy has played an important role in limiting ISIS’s territorial expansion. The United States and its allies have conducted airstrikes, targeted financial resources, and used special operations in limiting the extent of ISIS’s territorial control. Limiting territorial expansion lies at the heart of a containment strategy, and it also requires recognizing a continued ISIS presence in certain areas of Iraq and Syria.

Second, ISIS is an ideological movement, similar to Al Qaeda in that it is driven by and legitimized through its ideas. ISIS’s religious ideology is a fundamental source of its power and energy. Like the Soviet Union, ISIS’s ideology is used to justify its rule and its foreign policies. Where ISIS is similar to Al Qaeda and differs from the Soviet Union is that its ideology provides inspiration and a program that aids in recruitment. ISIS has attracted foreign recruits and developed an extremely sophisticated propaganda machine. ISIS poses a clear ideological threat in that it can inspire attacks in other places and destabilize domestic politics in neighboring states. While the United States has been effective in limited Islamic State’s territorial gains, the United States and its Western allies has been much less effective at undermining its ideological appeal.

Going after the ideological appeal of extremist groups has proven much more challenging and after a decade and a half, it is difficult to point to many tangible successes. The Bush administration tried to contain the ideological threat through winning the hearts and minds in the war of ideas. Current efforts, such as counter-messaging and offensive cyber operations, try to undermine ISIS’s ideological appeal and mitigate further radicalization, but the measures of effectiveness are still unclear.

Third, ISIS is an international terrorist organization. Its ideological and military activities are transnational, as attacks in Paris, Beirut, Tunis, Ankara, the Sinai, San Bernardino and Brussels make this abundantly clear. It is an international terrorist organization that includes threats from lone wolves and foreign recruits and networks.

What Can We Do?

The United States’ policy toward ISIS should be based on realistic expectations. First, it should realize that the United States can contain ISIS as a state or an insurgent group, but it cannot contain its ideology. Since the adversary is both a state and a terrorist group, a containment strategy requires preventing the state from expanding its territorial control and weakening the organization from within. Kinetic operations should be seen in this context. These operations are important for degrading the organization but insufficient for its defeat.

Second, the United States can prevent ISIS’s expansion in the peripheral areas by bolstering communal resilience to contain its transnational affiliates. Since communities are the lifeblood of terrorist groups, we must contain and “degrade” their appeal in the context of transnational affiliations. Terrorist groups need their communities for financial and personnel resources, safe havens, and intelligence. The United States government should continue to support programs that aim to make communities inhospitable to terrorist groups and bolster their resilience. This local containment strategy will make it much more difficult for ISIS to expand territorially.

Third, the United States should continue to dedicate the necessary resources and intelligence to prevent attacks on the United States and citizens abroad. This policy has important domestic and national-security implications. Every attack on the U.S. homeland brings out xenophobic tendencies, which are inherently anti-American and challenge the fabric of a multiethnic society.

Containment is insufficient to address the full range of threats ISIS poses. Bringing Kennan back in tells us that containment is a limited strategy that doesn’t seek destruction of the enemy. It is possible to limit ISIS’s expansion and weaken its hold over territory, but because ISIS is also an an ideological movement and a transnational terrorist organization, defeat is not possible through containment.

The populist alternatives, carpet bombing ISIS or launching a ground invasion, also do not recognize the multifaceted threat posed by ISIS. In fact, these solutions may do harm than good and have the potential to broaden and deepen community support for militant groups. While ISIS is a different adversary, these lessons from from the Cold War can be useful for thinking about how to best counter the threat posed by ISIS.

Jenna Jordan is an assistant professor in the Sam Nunn School of International Affairs at the Georgia Institute of Technology and a former research fellow at the Chicago Project on Security and Terrorism. She has published on terrorism and leadership targeting. You can follow her on Twitter @JennaEJordan. Lawrence Rubin is an associate professor in the Sam Nunn School of International Affairs at the Georgia Institute of Technology. He is the author of Islam in the Balance: Ideational Threats in Arab Politics (Stanford University Press, 2014) and Terrorist Rehabilitation and Counter-Radicalisation: New Approaches to Counter-terrorism (Routledge 2011). He is also the Associate Editor of the journal Terrorism and Political Violence. You can follow him on Twitter @lprubin73.

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