Military Times reported Monday that Secretary of Defense Mattis,

appearing on Capitol Hill Tuesday alongside Chairman of the Joint Chiefs of Staff Gen. Joe Dunford told a pair of congressional hearings that the White House gave him a free hand to reconsider the rules of engagement and alter them to speed the battle against the Taliban if need be.

Specifically, Mattis indicated that U.S. forces are now permitted to employ air power without a requirement that the intended objects of attack be “proximate” to U.S. forces or U.S. advised Afghan forces. This “proximity” requirement, apparently imposed by the preceding rules of engagement (ROE), restricted the use of airpower to situations when “we have to basically be in contact with that enemy,” according to Mattis. Obviously perceived as unjustifiably restricting the ability of U.S. forces in Afghanistan to employ airpower most effectively to attack enemy targets, the restriction has been removed. And apparently Mattis believes this is already paying positive dividends. Specifically, he indicated, “You see some of the results of releasing our military from, for example, a proximity requirement — how close was the enemy to the Afghan or the U.S.-advised special forces . . . no longer the case, for example. So these kind of restrictions that did not allow us to employ the airpower fully have been removed, yes.”

This ROE change is almost certainly indicative of the Trump administration’s determination to enhance the effect of U.S. combat power in Afghanistan, especially given the uncontested control of the air. While Mattis did not go into detail on the origins of the proximity requirement, it almost certainly emerged from the U.S. effort to minimize Afghan civilian casualties resulting from both collateral damage and from mistakes.

Like all use of force decisions associated with counter-insurgency operations, which of these interests should be prioritized is an important and complex policy question. From a legal perspective, however, there is no requirement that employment of lethal airpower be restricted to only those situations where U.S. or Coalition forces are in close proximity to enemy forces. While such a requirement may enhance the certitude that the object of attack is in fact lawful, what the law demands is that this determination be reasonable, not absolutely accurate. And while the law may even require a commander to take steps to obtain higher levels of certitude in some circumstances, it does not require the commander to do so at the expense of much greater opportunities to attack enemy forces.  Nor does the change seem to signal a reduction in U.S. commitment to law of armed conflict targeting rules, most notably the distinction obligation, which requires parties to distinguish between “combatants” and civilians. Mattis emphasized that target identification, and not proximity, is now the decisive attack criteria: “If they are in an assembly area, a training camp, we know they are an enemy and they are going to threaten the Afghan government or our people, [Gen. John Nicholson, commander of U.S. Forces Afghanistan] has the wherewithal to make that decision.”

There is, of course, no prohibition against relaxing rules of engagement that are more restrictive than the law of armed conflict (LOAC). Although not specifically addressed, there is no reason to doubt the consistency of the new rules of engagement, as described, with the LOAC. If anything, the Secretary’s comments indicate that shifting the decisive attack criteria from a proximity requirement to a LOAC based threat identification requirement. From an operational perspective, this seems to indicate a conclusion that the more restrictive proximity requirement was providing the enemy with an unjustified windfall of protection from some of the most effective and responsive combat capability in the U.S. commander’s arsenal.

Some may question the validity of this change, viewing it as a move that will unnecessarily dilute the protection of the civilian population. But there are many reasons to think that risk to civilians, or the mitigation of that risk resulting from the proximity rule, was carefully considered as part of the deliberative process that produced this ROE modification. Any suggestion that this modification reflects a new type of indifference toward the risk of civilian casualties would be inconsistent with counter-insurgency (COIN) doctrine and experience, which places an especially high value on civilian risk mitigation. (Mattis co-wrote the book on COIN including the imperative to reduce civilian casualties.) In testifying before the House Armed Services Committee, Mattis said:

[S]pecifically, we are no longer bound by the need for proximity to our forces. … At the same time, we do not want this to be misinterpreted into a laissez-faire use of fire support when we’re fighting wars where the enemy intentionally hides among innocents.
It is still very much aligned with our effort to do everything humanly possible to prevent the death or injury of innocent people, women and children, villages, this sort of thing.

Indeed, mitigating civilian risk may in fact be part of the “military advantage” commanders seek to achieve during the execution of combat operations during COIN. A proximity requirement for use of airpower does mitigate civilian risk by limiting situations when airpower is employed, and ostensibly by increasing the quality of threat identification. In this sense, it functions as a civilian risk mitigation precaution. But there is no reason to believe that airpower cannot be employed in other situations without an analogous commitment to civilian risk mitigation.

Relaxing the ROE to allow for an expanded use of airpower must, therefore, be coupled with a commitment to carefully implement other precautionary measures to ensure targeting operations do not produce an unintended effect inconsistent with COIN objectives. As I just mentioned, Secretary Mattis indicated that the ROE modification now allows for the application of decisive combat power against obvious Taliban targets, such as assembly areas and training camps. This seems like a logical development in a recalibration of operational authority to achieve the strategic objective of regaining the initiative in the seemingly endless fight against this resilient and adaptive enemy. What’s more, this may also reflect a recognition that more restrictive ROE may in some cases produce the perverse effect of increasing civilian risk by allowing the enemy to operate beyond the “proximity” range with impunity. Indeed, the reality that more aggressive use of force may at times produce a net gain in civilian protection is acknowledged in Paragraph 5.12.3 of the Department of Defense Law of War Manual, which provides:

Determining whether the expected incidental harm is excessive does not necessarily lend itself to quantitative analysis because the comparison is often between unlike quantities and values. The evaluation of expected incidental harm in relation to expected military advantage intrinsically involves both professional military judgments as well as moral and ethical judgments evaluating the risks to human life (e.g., civilians at risk from the attack, friendly forces or civilians at risk if the attack is not taken).

However, even if this factored into the decision to modify the ROE, we should hope and indeed expect that the elimination of the proximity requirement will lead to a “doubling down” on other precautionary measures, such as target identification efforts, attack timing and tactics to mitigate civilian risk, and ensuring the pilots charged with executing attacks are provided sufficient information to be able to meaningfully implement their individual obligation to cancel or suspend any attack anticipated to produce civilian casualties that are excessive compared to the anticipated military advantage.

This ROE shift is important, not only because it will ideally produce the intended detrimental effect on the enemy, but also because it serves as a reminder that ROE must be inherently mission responsive. COIN requires carefully calibrated uses of combat power, but it is a myth that COIN always requires minimized use of force. The challenge for commanders conducting COIN operations may require an increased emphasis on civilian risk mitigation, but mission accomplishment will, like any other combat operation, require the careful allocation of combat power to achieve operational and tactical objectives. COIN ROE must effectively balance these two interests, but should never be viewed as immutable. What this change ultimately reflects is the determination that the balance between these interests had not in fact been effectively calibrated by the proximity requirement, and that removing that restriction was necessary to better achieve operational and tactical objectives.

Will civilians face increased risk of accidental distinction errors or incidental injury and collateral damage as the result of this change? Perhaps (although the urgency of attack when U.S. or Coalition forces are actually in contact with the enemy may actually increase that risk because of the perceived importance of attack execution). But consistent with the LOAC, that is a risk that commanders are entrusted to weigh and to accept when justified by the dictates of mission accomplishment. Whatever else may evolve in our ongoing Afghan mission, it seems that maximizing the effect of superior U.S. combat power will be an increased priority.