(Editor’s Note: This is the second of three articles on how the lines have blurred between U.S. military operating procedures for use of force in hot war zones versus outside areas of active hostilities and how the executive branch and Congress might better govern operations going forward. The first article outlined how and why standards evolved after 9/11 and into President Barack Obama’s second term.)

The ink had barely dried on President Barack Obama’s 2013 Presidential Policy Guidance (PPG) establishing a separate set of operating procedures for direct military action against terrorist targets outside of areas of active hostilities, when the distinctions between those and areas where active hostilities were taking place began to blur even more than in the text itself. That led to the muddy middle where the United States finds itself today.

On the one hand, with the exception of the Afghanistan-Pakistan border region, progress stagnated or reversed within two years of the release of the Guidance in virtually every location that constituted a non-traditional battlefield at the time. In Yemen, the progress that had been made since President Abdrabbuh Mansur Hadi took power in 2012 had unraveled by late 2014, when the Houthis occupied the capital Sanaa. A full-scale civil war erupted after they overthrew Hadi in early 2015. Saudi and Emirati forces unleashed a potent and indiscriminate air campaign against the Houthis, while AQAP sought to leverage the chaos to seize ground and expand its operations.

In Somalia, as the fledgling government and the African Union continued to make halting progress against al-Shabaab in Somalia, the group lashed out with increased regional operations. Its attacks included the audacious assault in September 2013 on the Westgate mall in Nairobi, Kenya, that left more than 60 dead and nearly 200 wounded. Around the same time, diplomatic efforts to resolve the Mali-Taureg conflict, which AQIM and other groups had leveraged to strengthen their foothold in the region, fell apart, and AQIM deepened its safe haven

The fight expanded into other countries and in messy and unexpected ways. The security situation deteriorated rapidly in Libya following the NATO-led intervention. As the post-Qadhafi government devolved into infighting and outright violent conflict, various Islamic extremist militias exerted ever greater power. By late 2014, ISIS had set down roots in the country and occupied key cities along Libya’s coast; a ragtag group of local militias with limited government support appeared to be the only resistance to their gains.

The military also took advantage of authorities granted to it by Congress – first Section 1208 and then its successor, 127e – that provided funding for U.S. special operations forces to support partner forces – both state and non-state – that were engaged in counterterrorism operations. In practice, this helped enable the expansion of advise-and-assist and accompany operations that sometimes put U.S. troops in the position of having to use force either to defend themselves or their partners.

On the other hand, in hot war zones, the United States began to shift away from full-spectrum counterinsurgency operations toward a campaign of intensive air strikes and operational support to partner forces. After surging troops into Afghanistan, the Obama administration began a phased withdrawal of most combat forces. The decision reflected some progress in the counterinsurgency campaign but more frustration with the long duration of the war and a sense that it was time for the Afghan government to shoulder more of the burden. Remaining U.S. troops were dedicated to supporting Afghan government forces as part of a train, advise, and assist mission, or conducting limited counterterrorism operations.

Similarly, when the United States reengaged in Iraq in 2014 and, later that year, began conducting operations in Syria to counter the Islamic State of Iraq and al-Sham (ISIS), U.S. policymakers were not about to recommit large numbers of combat forces. Instead, although the administration qualified Iraq and Syria as a hot war zone, it opted for a paradigm in which U.S. forces provided intensive training, advice, and operational assistance to local forces, complemented by a robust air campaign.

In sum, within two years of the PPG’s release, in virtually every region outside an area of active hostilities where the United States faced a terrorist threat, that threat grew stronger and conflicts intensified substantially. In most cases, the United States ratcheted up air strikes and expanded its deployments of embedded advisors in response. In traditional war zones, war-weary policymakers began to draw down ground combat forces and lean more on air strikes and embedded advisors.

The differences between the use of force in traditional and non-traditional battlefields were less and less oriented around a bright line. Rather they existed on a continuum informed by the intensity of the threat, the operating environment, and the capabilities of partners, with U.S. efforts throttled up or down accordingly.

Deepening Tensions

The new operational models for both why and how the United States used force outside areas of active hostilities created tensions and challenges that have only deepened in the past few years.

First, deeper integration with partner forces has meant putting more U.S. forces in harm’s way. For example, the United States deployed advisors to help partner forces in the fight against al-Shabaab in Somalia, and launched an advisory and operational support campaign to aid Emirati and irregular Yemeni forces in their fight against AQAP. As a result, policymakers have had to grapple with the increasing possibility of U.S. casualties, the geopolitical consequences of increased deployment of U.S. military personnel, and the challenges of managing partners who do not abide by the same high standards of conduct that U.S. forces do.

Second, putting U.S. forces in harm’s way also meant that the U.S. military was much more likely to have to use force to protect them if they came under attack. Air strikes increased in Somalia – not as unilateral action against AQAP or al-Shabaab, but in “collective self-defense” of partner forces that U.S. troops were advising and assisting.

Finally, expanding operational support to partner forces raised the question of why the United States could not conduct strikes solely in offensive support of partners outside traditional war zones, rather than requiring a threat to U.S. persons or a valid claim of collective self-defense. Considering the U.S. emphasis on working by, with, and through partners, targeted air support seemed to some like a natural progression from providing other forms of operational support.

There was also a perceived growing need for such air support. In Libya, for example, needing more pressure than the PPG would allow against a growing ISIS threat, the Obama administration declared parts of the country to be areas of active hostilities, effectively exempting them from the PPG and allowing for an intensive campaign of air support to Libyan forces in their fight against ISIS. This decision highlighted how the framework for careful constraints on U.S. operations outside of Iraq, Syria, and Afghanistan was straining under the pressure of an expanding set of more dangerous and intensive conflicts.

Trump Loosens the Leash

U.S. policymakers struggled with these dynamics during the final years of the Obama administration, trying to reconcile new ways of using force in response to the evolving threat outside areas of active hostilities with the increasingly ill-fitting policy frameworks they had labored to create. Regardless of who won the White House in 2016, the ways in which the United States used force in non-traditional battlefields was likely to change.

Trump came to office promising maximum operational flexibility for the military, and almost immediately news reports emerged he was moving to suspend the PPG for six months to allow for a policy review. The Trump administration loosened targeting rules outside areas of active hostilities while the review was in progress, and approved more intensive special operations.

News reports indicate that the administration ultimately replaced the PPG with a slimmed-down Principles, Standards, and Procedures document, which reportedly retains some of the policy imperatives of the PPG and dispenses with others. The new rules reportedly maintain the construct of areas of active hostilities versus locations outside areas of active hostilities, and is believed to retain the requirement for near certainty of no civilian casualties for operations in the latter.

However, the changes also appear to have lowered the threshold for taking action in these places. Specifically, Trump reportedly removed the standard that a target must pose a continuing, imminent threat to U.S. persons, and reportedly reduced the required confidence that the intended target is in the strike zone from “near” to “reasonable” certainty. (We don’t know whether “collective self-defense” was included in the new policy, but its seemingly expanding concept has raised questions, including from Congress in late 2018, about creating a loophole in the use-of-force framework, as well as legal questions about the range of individuals that the United States might use force against.)

The president also reportedly delegated decision-making about the day-to-day use of direct action to lower levels of seniority. If these reports are true, then it seems that the administration’s approach has been to establish a baseline for limited direct action, while allowing for significant surges in strikes to support partners and inflict strategic losses on terrorist foot soldiers. It’s unclear if those lower-level commanders can approve periodic surges in strikes or air support to partners or whether such more intensive support requires a policy decision, raising questions about the interplay of policy and operations in this administration.

Intensifying Operations Without a Commensurate Framework

What have these policy changes meant in practice? U.S. military forces in Afghanistan remain split, with roughly half conducting counterterrorism operations and the other half advising and assisting Afghan partners. Airstrikes are conducted against shared targets. The U.S. military has adopted a similar advise-and-assist and targeted-airstrike model in Iraq and Syria (for the time being), although the total number of forces in these countries is lower than in Afghanistan.

Limited transparency from the Trump administration makes it difficult to assess operations outside areas of active hostilities, but news accounts suggests a surge in operations without a clear framework. News reports suggest the U.S. military has conducted a higher tempo of partnered operations and advise-and-assist missions in Yemen, Somalia, and various countries in the Sahel since Trump took office. Reports also suggest that the administration has seriously undercounted the civilian casualties that have resulted from these operations. Several operations have resulted in the deaths of American forces, including in Yemen, Somalia, and Niger. Beyond commando raids, drone strikes have also surged in Yemen and Somalia, presumably to help partner forces weaken AQAP and al-Shabaab, respectively. Outside groups have noted an uptick in civilian casualties across all theaters. In short, the administration is increasingly applying the same tools to areas of active hostilities and everywhere else; the distinction is around intensity of operations.

The Trump team deserves some credit for adapting operations to the evolving threat, but it does not appear that well-considered frameworks to govern these operations have kept pace. It remains necessary to keep certain guard rails on the use of air strikes to deal with some of the problems the PPG was developed to address, including excessive civilian casualties, and the tendency from operators to use force on any small threat rather than the most significant ones. The escalation in strikes during the past two years, and apparent increase in civilian casualties, suggests that such guard rails may not be fixed as firmly in place as they need to be.

There are new challenges to address as well: the temptation to become the permanent air force for partners, the lack of a threshold for strikes when U.S. forces are not in imminent danger, the need for clear thresholds of what should trigger risky advise-and-assist deployments, and a rubric for determining the rules of engagement for these missions.

(The third and final installment of this series will propose a framework governing counterterrorism operations going forward.)

IMAGE: A picture taken near the Iraqi city of Qaim at the Iraqi-Syrian border on November 11, 2018, shows US Army vehicles patrolling the Syrian side of the border.  (Photo by AHMAD AL-RUBAYE/AFP/Getty Images)