On Friday, Peter Bergen and David Sterman wrote an article for CNN Opinion entitled, “ISIS Threat to U.S. Mostly Hype.” (Bergen is also CNN’s national security analyst.) The authors correctly show that U.S. officials have at times inflated the threat that ISIL poses to the American homeland. Defense Secretary Hagel, for example, exaggerated the number of Americans fighting with ISIL (he said 100), which the Pentagon soon corrected (100 is the total of Americans fighting for any of the groups in Syria). But Bergen and Sterman also make a major misstep where they expend most of their analytic attention: They tell their readers not to worry as much about the threat of Americans fighting with ISIL, because several more Americans fought with Al-Shabaab in Somalia since 2006 and never carried out a terrorist attack on the US homeland.

The comparison with Al-Shabaab is fundamentally flawed. [See my debate on Twitter with Peter Singer on this topic.]

Why is the comparison with Al-Shabaab a false one?  In this post, I discuss four factors.

(1) ISIL as a unified organization has openly vowed to attack the United States;

(2) ISIL has engaged in targeted killing of Americans;

(3) The United States is directly in armed conflict with ISIL;

(4) ISIL’s revenue stream is greater than any other terrorist group in the world.

Each of these factors is obviously critical to evaluating the ISIL threat, including the threat posed by Americans joining them in the fight. Bergen and Sterman do not discuss any of these factors. Yet none of these factors are the same for Al-Shabaab over the years that Americans joined that organization.

(Note: Bergen and Sterman analyze only American citizens joining ISIL, and do not also include Europeans who can enter the United States without a visa.)

Before getting into a bit more detail, it’s important to note that analysis of the ISIL threat to the United States can cut in different directions in terms of its policy implications. On the one hand, if the threat to the U.S. from Americans joining ISIL is low-grade it undermines the administration’s justification for continuing and expanding operations against ISIL in Iraq or launching into Syria. On the other hand, if the threat to the U.S. from Americans joining ISIL is high—e.g., due to blowback for our taking the fight to ISIL—that’s a reason to consider minimizing or retracting U.S. military operations. The important point is not to let one’s preferred policy outcomes pollute the empirical analysis. Conclusions about the threat of Americans joining ISIL cuts both ways.

Let’s turn to the four factors—and the considerable differences between ISIL and Al-Shabaab.

1. ISIL vows to attack the United States and target Americans

On August 19, 2014, ISIL reportedly “warned the United States it will attack Americans ‘in any place’ if the raids hit its militants” (Reuters). The statement accompanied a video of an American beheaded during the US occupation of Iraq (more below on ISIL’s predecessor, Al Qaeda in Iraq, carrying out such beheadings of Americans). The statement also read: “we will drown you all in blood.”

In an interview with VICE Media before US airstrikes began, ISIL’s Press Officer said, “I say to America, that the Islamic Caliphate has been established. And we will not stop. Don’t be cowards and attack us with drones. Instead send your soldiers, the ones we humiliated in Iraq. We will humiliate them everywhere, God willing, and we will raise the flag of Allah in the White House.” (Caution: Other media outlets have exaggerated that statement by excluding the reference to American ground troops, which might make it a conditional threat.)

In its final email sent before killing Jamey’s Foley, ISIL said (emphasis in original):

“We have left you alone since your disgraceful defeat in Iraq. We did not interfere in your country or attack your citizens while they were safe in their homes despite our capability to do so!

You do not spare our weak, elderly, women or children so we will NOT spare yours!
You and your citizens will pay the price of your bombings!”

These statements should be understood in the context of earlier ones by ISIL leader, Abu Bakr al-Baghdadi, after he assumed leadership of the group in 2010 when it was under the name “Al Qaeda in Iraq” (AQI). In 2012, Baghdadi stated his intent to attack inside the United States: “Soon you will witness them in the heart of your homeland, as our war with you has just begun, and so await them.” And this: “The Mujahideen have departed to pursue your fleeing army, and they have sworn to make you face more severe punishments than those dealt to you by Osama (bin Laden).”

At that time (July 2012), the LA Times (Brian Bennett) reported, that “the militant organization that was once the scourge of the U.S. military campaign in Iraq … has set its sights on launching attacks in the United States, intelligence officials said. … several associates of the group have been arrested in the U.S. and Canada in the last two years, said American officials, a sign that the organization has tried to establish a network in North America.”

Admittedly, the AQI period was context dependent. That is, AQI’s threat to Americans involved a response to US forces inside Iraq. And, similarly the more recent statements by ISIL were also in reaction to the U.S. military fighting inside Iraq. But that’s part of the point. You can’t put the genie back in the bottle. Any reasonable threat assessment of ISIL needs to take into account current conditions, in which the US has engaged them directly in the fight (see also #3 below).

How does this compare to Al-Shabab? The group, including parts of its leadership, have long been divided over whether to direct hostilities toward the United States and the West. And, indeed, the leadership was far less inclined to take any fight to Americans at the time US citizens started joining Al-Shabaab (see this synopsis of revelations in Dan Klaidman’s book).

2. ISIL attacks on Americans

This factor is most obvious. ISIL has recently killed two American journalists. In another piece for CNN last month, Bergen and Sterman acknowledged that “ISIS’ predecessor, al Qaeda in Iraq … did bomb three American hotels in Jordan in 2005.” AQI also beheaded other Americans in Iraq during that period.

What about Al-Shabaab? There are no comparable cases of attacking American targets.

3. The United States is in armed conflict with ISIL

The United States is now engaged directly in an armed conflict with ISIL, having launched well over 130 airstrikes. In contrast, the administration has very carefully avoided engaging directly in a conflict with Al-Shabaab. We have targeted only those members with a dual membership in AQ central. I discuss this distinction in a post–“Targeting Al-Shabaab’s Godane is not the same as targeting Al-Shabaab”–which also summarizes posts by other Just Security editors and recent testimony by the Defense Department’s General Counsel. Indeed, the administration has never publicly claimed legal authority to fight Al-Shabaab.

The US policy and legal decision to avoid attacking Al-Shabaab directly has meant that US forces have not gone after infrastructure or weaponry, command and control centers, foot soldiers, and the like. Other governments and institutions—such as Kenya and the African Union (backed up by the UN Security Council)—are more the face of the conflict with Al-Shabaab. The United States has simply not taken the fight to Al-Shabaab in anything that compares, in law or policy, to the direct armed conflict in which we are engaged with ISIL.

In short: right now, what you’re seeing with ISIL – that’s what it looks like when the U.S. engages in an armed conflict and is going after a group. This is a difference in kind as well as magnitude.

Admittedly the U.S. targeting of AQ members in Somalia over the past several years (see the Long War Journal’s list of strikes) has been sporadic but, indeed, significant. Those occurrences, however, also show the lines that we have not crossed. And those lines make a considerable difference when it comes to threats assessments of blowback.

4. ISIL’s revenue stream is greater than any other terrorist group in the world

Finally, any analysis of the threat of Americans (and Europeans) joining ISIL compared to Al-Shabaab surely should take into account the material resources of the two organizations. According to all reports ISIL is the most highly funded terrorist organization in the world, reaping several million dollars from oil revenues alone each week. To be sure, Al-Shabaab has ranked highly in the past among the world’s most well-funded terrorist outfits. But the ability of ISIL to project force against US targets is surely far stronger than Al-Shabaab’s along this dimension.

 * * *

One might support or oppose expansive US military operations against ISIL. Regardless of that position, it is best to reach the conclusion with a realistic assessment of the empirics of the ISIL threat. (I have, for example, previously drawn attention to perspectives that suggest US and UK officials have exaggerated the ISIL threat.) I appreciate Bergen and Sterman’s suggesting ways to analyze the risk. Their comparison to Al-Shabaab, however, can help us identify the true scope of the ISIL threat only when these other factors are admitted into the equation.