Surely, deploying “earlier and smaller” is far more preferable to “later and bigger.” Then why does the United States persistently prove reluctant to do so? Often, this failure comes down to a lack of strategic foresight. When dealing with countless local terrorists, narrow insurgencies or geographically limited violent criminal groups, the best option for the United States is usually to decline to involve itself militarily in matters without a clear link to vital U.S. national-security interests. But Salafi jihadist terrorists differ in at least one critical respect from other terrorists—even from other Muslim terrorist groups. Once they possess territory, sanctuary that allows them to act with impunity, they will eventually conduct external attacks. This evolution is inexorably driven by a dangerous combination of their own brand of religious ideology, the public narrative they are trying to project globally and the internal incentives that reward individual leaders who direct such attacks. In some places, it has taken longer than others for them to reach this point, but unless they are denied such sanctuary altogether, they will inevitably commit terrorist attacks abroad.

This was true when Al Qaeda gained sanctuary in Afghanistan and then Pakistan, when Al Qaeda in the Arabian Peninsula (AQAP) gained sanctuary in Yemen, and when the Islamic State gained sanctuary in Syria and Iraq. This was true whether in was in the context of Osama bin Laden’s prioritization of attacks against the “far enemy” before the “near enemy,” or in the context of Abu Bakr al-Baghdadi’s direction to attack the Shia, then the Saudi monarchy, and then the “crusaders and their bases.” In each case there were American analysts both inside and outside of government who initially argued that the terrorists’ goals were merely local; in each instance they were sadly proven wrong. But this dynamic does help explain why the United States has previously been slow to begin necessary indirect-action campaigns.

Furthermore, given perceived limits on U.S. resources it can be tempting for policymakers to focus their attention on the most immediately threatening terrorist groups and affiliates: those who have already successfully directed external attacks. But even a superficial review of budget levels over the past decade shows that the Congress has been remarkably forthcoming with military and other security budgets—indeed, perhaps too forthcoming—and thus the total amount of resources available is rarely the true limiting factor. More significant has been the executive branch’s failure to strategically prioritize within the counterterrorism assistance budgets provided, which are usually spread across a large number of differing bureaus and offices in multiple departments and agencies, each of which is institutionally reluctant to be told how to spend “its” money.

A more pernicious impediment is the concern among policymakers, sometimes deeply held but rarely spoken, that a campaign of indirect action will trigger a slippery slope that inevitably leads to a large conventional military deployment. This was a foundational lesson that many liberals took from the Vietnam War. Nevertheless, those who study indirect action argue the exact opposite—that a small deployment of military advisers is more often the critical element that prevents the later need for a large conventional military deployment.

 

BUT CONCERNS about a slippery slope shouldn’t be dismissed out of hand. Rather, U.S. policymakers should candidly recognize the risk and identify steps to mitigate it. Here America’s experience with Plan Colombia is instructive. When the Congress first approved the plan, during the final year of the Clinton administration and after much debate, it imposed an unsolicited legal limit on the number of U.S. military personnel and civilian contractors allowed in country: four hundred in each category. After a similarly robust debate, the Congress modestly increased the cap during the Bush administration, to eight hundred and six hundred, respectively. At the same time, aside from a prohibition on U.S. forces being involved in combat operations, the law did not micromanage the types of assistance that could be provided.

This combination of clear limits and broad authority incentivized creative military planning to adhere to the legal caps and accelerate the building of Colombian capabilities. The fact that these personnel ceilings were enshrined in specific law for Plan Colombia made the legislative and executive branches full partners in this indirect-action campaign and precluded the military from going back to the president for an increase in forces at the first sight of a roadblock. The number of U.S. personnel in Colombia, while still several orders of magnitude smaller than the prior conventional deployments in Iraq and Afghanistan, was the largest sustained indirect-action campaign until recent deployments to Iraq.

At this point in the policymaking process, concerns are also typically expressed about the nature of the force that the United States is to support. It is not unusual for allegations of corruption, criminal activity and gross human-rights abuses to surface, especially when considering irregular fighters or poorly trained regular military units. These concerns must always be taken seriously, both for moral reasons and because widespread corruption and criminality can undermine the military effectiveness of these units and cause them to lose the support of the wider local population. The Leahy Law provides a workable a framework for dealing with such allegations, should U.S. policymakers be willing to accept the domestic political risks inherent in these types of missions.

But a policy that requires perfection before partnering is usually a policy that doesn’t allow for indirect action at all—and thus increases the likelihood that the United States will eventually have to rely on its own conventional land forces to meet its counterterrorism objectives. This, of course, is exactly the outcome that many strategic planners are trying to forestall. Fortunately, the best way to mitigate human-rights violations over time is through thorough interagency vetting and active U.S. mentoring that accompany building relatively small, specialized forces. The less hands-on the U.S. support, the more likely it is that it will be misused. And the more American forces are trusted by the locals, the more they are likely to react thoughtfully and decisively to any accusations of human-rights impropriety.

Domestic political considerations have also hampered imperative indirect-action campaigns. After acceding to the Oval Office on an antiwar platform, President Obama was understandably reluctant to take steps that could misconstrued as new military fronts against terrorists. Asking a politician to risk the perception of flip-flopping—especially on the subject of war and peace—is never an easy sell. It took the Bush administration far too long to reverse its initial counterproductive prosecution of the Iraq War, and it took the Obama administration too long to recognize the need to send U.S. special-operations forces back into Iraq after they were withdrawn. Moreover, the American public does not easily distinguish between combat operations and advisory missions, especially if both can put U.S. military personnel at risk. Impassioned promises of “no boots on the ground” are as politically comforting as they are intellectually inchoate.

Once policymakers decide to send a relatively small contingent to support others fighting terrorists, they must also determine the range of support that American forces are allowed to provide. These can be roughly divided into equipping, training, advising, assisting and accompanying missions. At one end of this spectrum, the U.S. government simply sells or otherwise provides military or other specialized equipment and may or may not itself offer training on the proper use of that equipment. At the other end of this spectrum, U.S. forces help their counterparts plan operations against a specific terrorist target, provide a range of direct support for those operations and accompany them to the objective, allowing for continuous, real-time tactical advice—just short of joining them “on target” during the military operation itself. These are not combat operations but walk right up to that line, and in doing so, put U.S. forces in harm’s way. Indirect-action campaigns that allow the full spectrum of these activities typically maximize their overall effectiveness and accelerate the speed by which foreign forces become independently capable of successful counterterrorism operations. And this acceleration of local capability is the most effective way to limit the risk of the slippery slope that leads to a much larger conventional military deployment.

Building foreign surrogate units often requires a commitment to enable them when they get in the field, for operational as well as moral reasons. This means ensuring that they have everything U.S. forces would: command, control and communications; intelligence, surveillance and reconnaissance; medical-evacuation capabilities; and, when necessary, lift, fire and close air support.

Sometimes, for its own understandable reasons, the host government limits the range of support. But just as often, U.S. policymakers have imposed their own constraints—sometimes in direct opposition to partners’ requests. The further up the spectrum of support, the greater the “risk to force” even as “risk to mission” is mitigated. Since U.S. forces in small numbers are accompanying their foreign partners inside hostile territory, they must always be allowed to defend themselves if attacked. And since they must have rules of engagement defining the circumstances under which they can come to the defense of their surrogate unit, these indirect support and enabling missions always place American personnel in danger, even if they are not formally considered U.S. combat missions. And in a domestic media environment haunted by the specter of “Black Hawk Down” in Somalia and, more recently, the death of Amb. J. Christopher Stevens in Benghazi, it is not surprising that U.S. policymakers sometimes hesitate before accepting this “risk to force” and its wider political ramifications.