An Operational Perspective of Military Advantage and Proportionality

Scholars have described the law of targeting as lying at the heart of the law of armed conflict (LOAC). Within the law of targeting, the rule of proportionality requires military planners, commanders, and those executing attacks to assess whether the expected harm to civilians and civilian objects is excessive in relation to the anticipated military advantage. However, while academic literature often examines the civilian harm considerations, it lacks a thorough analysis of the military advantage. Professor Yoram Dinstein noted that the “military advantage may not always be easily gauged. In many instances, the benefits accruing from an attack against a military objective depend on the interpretation of the operational picture at the time of action” (para. 543).

As a result, it is challenging for outside observers to identify, understand, and quantify the anticipated military advantage of an attack and determine, ex post facto, whether the attack complied with the rule of proportionality. While the specifics of an individual military operation and the factors a commander relied upon will typically remain unknown (e.g., classified), military doctrine sheds light on how commanders and their staff plan military operations and the general considerations they use when approving attacks. This post seeks to identify some factors commanders and planners may consider when evaluating an attack’s military advantage and explain how those individuals may use the factors when conducting a proportionality analysis.

The Law

The law of targeting encompasses four basic rules: distinction, precautions in attack, proportionality, and humanity, which are considered customary international law and are applicable in both international armed conflicts and non-international armed conflicts (see Schmitt and Widmar, p. 381). Within each rule, the military advantage of the attack is an important consideration. However, the rule of proportionality significantly emphasizes the anticipated military advantage and further requires an attacker to assess its value or weight (Dinstein, paras. 533–34).

Specifically, the rule of proportionality requires attackers to “refrain from deciding to launch any attack which may be expected to cause incidental loss of civilian life, injury to civilians, damage to civilian objects, or a combination thereof, which would be excessive in relation to the concrete and direct military advantage anticipated” (Additional Protocol I, art. 57(2)(a)(iii); see also U.S. Department of Defense (DoD) Law of War Manual, § 5.10). This rule “is not a balancing test nor a scale resting at equilibrium” (Schmitt, p. 15). Rather, the rule requires the attacker take a “systematic” or analytical approach that evaluates both the expected harm to civilians and civilian objects and the anticipated military advantage to ensure the former is not excessive in relation to the latter.

The rule of proportionality requires that the anticipated military advantage be “concrete and direct” (DoD, Law of War Manual, § 5.12.2; Dinstein, para. 348). In other words, the military advantage cannot be hypothetical or speculative. Specifically, “there must be a good faith expectation that the attack will make a relevant and proportional contribution to the goal of the military attack involved” (DoD Law of War Manual, § 5.12.2).

In addition, the military advantage does not have to be immediate and is not limited to a tactical advantage (DoD Law of War Manual, § 5.12.2, § 5.12.2.1). Instead, a commander may assess the military advantage of an attack “in the full context of the war strategy” (DoD Law of War Manual, § 5.12.2.1). Likewise, a commander can consider the military advantage within the context of the overall attack and not just from its isolated or individual parts (Dinstein, paras. 346–47; ICRC, Customary International Humanitarian Law study, rule 14). In other words, if a military operation includes multiple, simultaneous air strikes on the enemy’s communication infrastructure, the commander can view each strike’s military advantage within the overall operation’s context.

Finally, the commander’s evaluation of the anticipated military advantage “is appraised against the background of the ‘circumstances ruling at the time’ of action” (Dinstein, para. 352). As the DoD Law of War Manual notes, “the principle of proportionality does not preclude commanders from taking decisive action in doubtful cases, but commanders must make decisions in good faith on the basis of the information available to them” (§ 5.10.4). Therefore, a commander may rely on the intelligence available at the time of the attack, even if they are operating in a time or resource-constrained environment.

Factors

When evaluating the anticipated military advantage of an attack, commanders may consider certain factors to determine how the attack benefits or supports their military operations. Using those factors, commanders will then assess the weight or value of the anticipated military advantage and compare it to the expected collateral damage. The weight a commander gives the anticipated military advantage “is not an exact science” and is a “subjective evaluation” (Dinstein, paras. 533–34). However, commanders will typically look at the relative importance of each factor they relied upon within the context of the battlefield operations.

In the U.S. military, doctrine refers to the “fundamental principles … that guide the employment of … military forces in coordinated action toward a common objective” (U.S. Joint Chiefs of Staff, DoD Dictionary). Joint Publications and service-specific publications like Army Field Manuals codify military doctrine. Military leaders, both officers and non-commissioned officers, are trained in doctrine throughout their careers. Whether it is institutional training for mid-career officers, such as the Command and General Staff Officer’s Course or an Army Brigade-level exercise at a Combat Training Center, leaders constantly review, practice, and reinforce military warfighting doctrine. Therefore, we must look to military doctrine to understand the factors a commander may use to evaluate and weigh the military advantage of an attack.

Level of Warfare

The level of warfare an attack may affect will significantly impact the commander’s evaluation of the military advantage. There are three levels of warfare in military doctrine: strategic, operational, and tactical (Joint Publication 3-0, Joint Campaigns and Operations, p. I-11 (JP 3-0); Army Field Manual 3-0, Operations, § 1-58 (FM 3-0)). The strategic level of warfare consists of two sub-levels: national strategic and theater strategic.

The national strategic level is where senior civilian policymakers, political appointees, and Cabinet officials operate, such as those on the National Security Council (JP 3-0, p. I-11; FM 3-0, § 1-60). Military commanders, however, primarily operate at the theater strategic level and below. The theater strategic level is the level at which combatant commanders, such as the Commander of U.S. Central Command, and their staffs implement military-specific actions and synchronize those actions with other U.S. government organizations such as the U.S. Department of State to “fulfill policy aims within the assigned theater in support of the national strategy” (FM 3-0, § 1-61).

Below the strategic level are the operational and tactical levels. The operational level is where commanders plan and execute large military campaigns “to support [the] achievement of strategic objectives” (FM 3-0, § 1-62; see also JP 3-0, p. I-11). The tactical level is where “forces plan and execute battles and engagements to achieve military objectives. Activities at this level focus on tactics—the employment, ordered arrangement, and directed actions of forces in relation to each other” (FM 3-0, § 1-66; see also JP 3-0, p. I-11). In other words, the operational level links and organizes tactical battles and engagements with the strategic level’s objectives.

Each military operation or attack may affect one or all the levels of warfare. For example, a tactical-level commander may plan to destroy a bridge in enemy-held territory, critical for moving the enemy’s supplies and munitions. While this is a tactical operation, the effects of the attack (i.e., degrading the enemy’s ability to move supplies and munitions) may provide an operational-level military advantage. Destruction of the bridge may sever the enemy’s supply of food and ammunition to its front-line troops, allowing friendly forces to conduct a large-scale attack against the weakened enemy formations.

Similarly, attacks on high-value individuals (HVI) may have strategic-level effects. Examples of attacks on HVIs include Ukraine’s attacks on Russian General Officers and the United States’ attacks on Abu Musab al-Zarqawi, Abu Bakr al-Baghdadi, and Osama bin Laden. Senior military leaders are often instrumental in providing their subordinate forces with strategic-level direction and control, planning, inspiration, ideology, and resources. Therefore, a military commander may assess that a tactical operation to kill an enemy’s senior leader will have operational or strategic effects on the battlefield. Accordingly, a commander would likely evaluate the anticipated military advantage of an attack on the HVI much higher than other tactical-level attacks.

Consequently, the level of warfare an attack may affect is an important factor that commanders will likely consider. In addition, commanders may rely heavily on this factor when weighing the relative value of the anticipated military advantage of an attack. While the level of warfare alone is not determinative of the anticipated military advantage, generally, a commander will assess an attack that provides a strategic or operational advantage as having greater weight.

Type of Military Operation

The type of military operation can also affect the commander’s evaluation of the military advantage. Generally, military units conduct operations to achieve specific objectives. There are three categories of operations: offensive, defensive, and stability (FM 3-0, § 1-44; see also JP 3-0, p. IV-18). The type of operation and its objectives (e.g., seize or defend terrain) will determine the individual attacks a military unit will conduct. Accordingly, understanding the type of operation a unit is conducting will help determine the relative value or weight of an attack.

An offensive operation “is an operation to defeat or destroy enemy forces and gain control of terrain, resources, and population centers” (FM 3-0, § 1-45). Typically, offensive operations are when a military unit moves into enemy-held territory to destroy the defending enemy force and take control of the enemy’s key terrain or infrastructure. The U.S. Army’s “Thunder Run” into Baghdad, Iraq, in April 2003 was a highly successful offensive operation.

Defensive operations are effectively the opposite of offensive operations. In a defensive operation, a military force aims to repel an enemy’s offensive actions, maintain control over terrain, or protect critical infrastructure, populations, resources, etc. (FM 3-0, § 1-46). An example of a defensive operation is Ukraine’s nine-month defense of Bakhmut from Russian advances from August 2022 to March 2024.

Finally, stability operations “establish or maintain a secure environment and provide essential governmental services, emergency infrastructure reconstruction, and humanitarian relief” (FM 3-0, § 1-48). Stability operations may occur independently or after a military unit’s offensive or defensive operation when the unit intends to hold and control terrain in populated areas. During the conflicts in Iraq and Afghanistan, the U.S. military would conduct offensive operations to quickly and decisively defeat the adversary’s forces that occupied urban population centers. However, the U.S. military would spend years conducting stability operations, fighting the adversary’s insurgent forces, and attempting to provide the civilian population with security and essential governmental services (p. 131).

During offensive operations, commanders are trained to “seize, retain, and exploit the initiative” and maintain momentum (FM 3-0, Table 1-1, 6-232). An attack’s timing or target may allow a commander to maintain momentum, thus significantly enabling the offensive operation. Suppose an enemy tank is positioned on a hilltop next to multiple civilian homes. This enemy tank’s commanding view of the battlefield prevents a U.S. infantry battalion (approximately 1,000 troops) from moving forward to secure advantageous terrain. Destruction of the enemy tank as soon as possible would allow the infantry battalion to maintain momentum and not become pinned down. However, the destruction of the tank would also destroy the civilian homes and kill or injure any civilians inside. In this scenario, the attack on the tank would have a high military advantage and may be proportional despite the collateral damage the attack may cause.

Now, suppose the infantry battalion’s mission is to defend a town from an approaching enemy force. The battalion’s troops are spread out in defensive positions around the town’s perimeter. If an enemy tank slowly approaches the hidden friendly positions, there would certainly be a military advantage associated with destroying that tank. However, an attack on the tank may also destroy nearby civilian homes and injure or kill the civilians inside.

This scenario presents different operational and temporal considerations compared to the offensive operation. In a defensive operation, the tank may be less of a threat to the overall operation because the momentum of the friendly forces is not a concern. In addition, it is unlikely the tank could pin down an entire battalion spread out over a large area. Therefore, for the proportionality analysis, a commander may assign less weight to the military advantage of attacking the tank during a defensive operation than an offensive operation. If the expected collateral damage between the two scenarios remains the same, the lower anticipated military advantage may mean a strike on the tank is not proportional.

Center of Gravity

During operational planning, military planners will seek to identify the enemy’s center of gravity (COG). The enemy’s COG is its “source of power that provides moral or physical strength, freedom of action, or will to act… . A way to think about the center of gravity is that it is the primary entity that possesses the inherent capability to achieve the objective” (U.S. Army Field Manual 5-0, Planning and Orders Production, § 2-55 (FM 5-0); see also Joint Publication 5-0, Joint Planning, p. IV-22 (JP 5-0)). In other words, the COG is the thing that enables the enemy to achieve its goals.

The enemy’s COG can be different at different levels of warfare, and it may change during conflict as the enemy’s objectives change. At the tactical and operational levels of warfare, the enemy’s COG is almost always the most significant military force standing in the way of friendly forces achieving their objectives. However, at the theater strategic level, the enemy’s COG may include other things, such as an enemy’s strategic military leader (i.e., an HVI). For example, at the tactical level, a tank unit may be the enemy’s COG. However, the enemy’s air defense unit is the COG at the broader operational level because it prevents friendly forces from gaining air superiority over the battlefield. Once friendly forces destroy the enemy air defense unit, the enemy’s COG at the operational level would change. Therefore, analysis of the enemy’s COG is an ongoing process for military planners (JP 5-0, p. IV-23).

Once military planners identify the enemy’s COG, they develop decisive points. A decisive point is

key terrain, key event[s], critical factor[s], or function[s] that, when acted upon, enables commanders to gain a marked advantage over an enemy or contribute materially to achieving success… . The loss of a decisive point weakens a center of gravity and may expose more decisive points, eventually leading to an attack on the center of gravity itself (FM 5-0, § 2-57–58).

Put differently, decisive points often target the critical resources or vulnerabilities of the enemy’s COG. A decisive point could be a port facility for storing and transferring fuel used by the enemy COG or the electricity substations that power the enemy COG’s communication infrastructure. Once a military unit destroys those critical resources or vulnerabilities, the enemy’s COG is less effective or more vulnerable to attack. Consequently, commanders will generally assign greater weight to the anticipated military advantage of attacks on an enemy COG or on decisive points.

Risk

Military leaders and commanders always evaluate risk and risk mitigation during training, planning, and operations. Risk “is the exposure of someone or something valued to danger, harm, or loss” (FM 5-0, § 1-29). Risk, inherent in all military operations, can be a resource shortfall, an inherently dangerous infiltration method such as parachuting soldiers behind enemy lines, or an operation that exposes a friendly force’s flank to the enemy. For combat operations, risk generally breaks down into two categories: risk to the mission and risk to the force (FM 5-0, § 2-80). Risks to the mission are those things that would detrimentally impact mission accomplishment. Risks to the force are things that risk friendly forces’ life, health, or safety.

During operational planning, commanders and their staff will assess risk and attempt to mitigate it. However, the adage “the enemy gets a vote” applies during combat operations. Often, troops in combat will encounter the enemy in an unplanned or unexpected manner, such as an ambush. These situations significantly increase the risk to the mission and the risk to the force. Therefore, a commander will almost always evaluate the responding attacks on the enemy forces, often called self-defense strikes, as having a high military advantage because they protect the lives of friendly troops and prevent mission failure.

An illustration of risk as a factor is the Israeli hostage rescue operation in the Nuseirat area of Gaza in June 2024. During the operation, the hostage rescuers and freed hostages reportedly came under “fierce resistance” from Hamas fighters as they attempted to exfiltrate the area. As a result of Hamas’s unexpectedly intense attacks, Israeli forces responded with overwhelming force, presumably to protect their troops and the hostages as they escaped. However, Israel’s attacks also reportedly caused significant collateral damage. While this post does not assess the lawfulness of Israeli operations, this example illustrates how risk-to-mission and risk-to-force factors may influence a commander’s evaluation of the military advantage.

Time

Captain Wayne Hughes, a prominent naval warfare theorist, famously distilled the objective of modern maritime combat into three words: “attack effectively first” (pg. 17-18). Failing to do so results in defeat. Today, in the age of hypersonic missiles, artificial intelligence, and kamikaze drones, Captain Hughes’ statement remains deadly accurate and applicable in all the warfighting domains: land, maritime, air, space, and cyberspace (see FM 3-0, § 1-84; JP 3-0, p. IV-1). Indeed, General Joseph Dunford, the former Chairman of the Joint Chiefs of Staff, noted that “advancements in technology have accelerated the speed and complexity of war … [and] [a]s a result, decision space has collapsed.”

Consequently, time is a significant factor in evaluating and weighing the military advantage anticipated from an attack (see JP 5-0, para. IV-19). First, time is essential as it pertains to the commander’s ability to conduct an attack. That is, striking the enemy before it can strike friendly forces or defend itself. For example, if intelligence identifies an enemy’s road-mobile hypersonic missile launcher, a commander will likely evaluate an immediate strike on that target as having a very high military advantage. The hypersonic missile launcher is a valuable, strategic target, and its fleeting nature requires a timely attack. In addition, the commander must conduct the strike before the enemy fires the hypersonic missile to prevent the loss of friendly troops and equipment. Consequently, the advantage of the attack increases the sooner the strike occurs.

In addition, the timing or sequencing of attacks may be essential to a military operation’s success (JP 5-0, para. IV-19). In other words, coordinating attacks on a target or across the battlefield may create a greater military advantage. For example, if the military unit destroys the enemy’s air defense systems at the exact moment friendly bomber aircraft penetrate the enemy’s air space en route to bomb the enemy’s nuclear weapons facility, the military advantage of each missile strike significantly increases, so long as it occurs at a specific time.

Conversely, an attack that causes the enemy to pause or delay their decision-making process or slow down their ability to communicate decisions also has a significant military advantage. On the modern battlefield, seconds can mean life or death. Therefore, causing the enemy to take longer before they can conduct an attack is highly beneficial because it may prevent the enemy from firing effectively first. As a result, commanders will seek opportunities to insert uncertainty or doubt (often referred to as “friction” (Joint Publication 1, Volume 1, Joint Warfighting, p. II-12, 13)) into the enemy’s decision-making process.

Take, for instance, the Israeli pager and walkie-talkie attacks on Lebanese Hezbollah in September 2024. In addition to targeting enemy fighters, the psychological effect of the attacks caused the entire organization to abandon its communication devices (an effect that recently spread to Iran’s Revolutionary Guard Corps). As a result, Hezbollah senior leadership had to physically meet, which slowed down their decision-making and delayed communication of their decisions. Days later, Israel took advantage of this friction by conducting a rapid ground invasion into southern Lebanon, which met little resistance, and striking the senior leader meetings. In addition to their kinetic effects, the military advantage of the pager and walkie-talkie attacks likely also included the time and friction they injected into Hezbollah’s decision-making process.

Application of the Factors

Military commanders may rely on one or many factors when evaluating the anticipated military advantage of an attack. In addition, the weight a commander gives to each factor will vary depending on the circumstances. Therefore, understanding the context of the military operation is critical.

Suppose a special operations task force (SOTF) has identified an enemy senior military leader whose elimination will strategically impact the enemy’s ability to plan, coordinate, and execute military operations. After collecting intelligence on the enemy leader’s daily movements, the SOTF commander approves a plan to strike the enemy leader while he is driving in a rural area. To further limit collateral damage, the SOTF will use an armed MQ-9 Reaper drone firing a specialized Hellfire missile. However, just before the attack, by complete coincidence, the enemy leader stops and picks up a hitchhiker on the side of the road. Striking the enemy leader now will undoubtedly lead to the death or injury of the civilian hitchhiker. The SOTF commander must now quickly re-evaluate the law of targeting rules.

When conducting a new proportionality analysis, the commander will likely consider many factors. First, the strategic advantage of killing the enemy leader may be very high. For example, if the senior leader is instrumental in developing, resourcing, and coordinating the use of chemical weapons against friendly forces, then his death may provide a strategic advantage (see, e.g., here and here). Consequently, based on this singular factor, the SOTF commander could determine the anticipated military advantage of the attack is high enough that the death or injury of one civilian is not excessive.

However, time may also be a critical factor. The ability to strike the senior leader may be fleeting (i.e., he frequently changes his pattern of life). Or the senior leader may be planning to conduct an imminent attack on friendly forces. Consequently, the anticipated military advantage of the strike may be contingent on it occurring at a specific time because it affords the SOTF the best or only opportunity to find, track, and kill the senior leader. Likewise, the military advantage may significantly increase if the SOTF kills the senior leader before he executes the attack on friendly forces. Therefore, based on the strategic value of the strike and the time factor, the SOTF commander could determine that the death of one civilian is not excessive in relation to the anticipated military advantage.

However, the SOTF commander may factor in the effect the civilian death has on the overall military operation. For example, during counter-insurgency operations, civilian casualties may have a detrimental impact on the operation and “create tactical and operational gaps that insurgents can exploit” (Army Field Manual 3-24, Insurgencies and Countering Insurgencies, para. 1-57). As retired General Stanley McChrystal observed in Afghanistan, “[w]e’re going to lose this … war if we don’t stop killing civilians” (p. 310). In other words, avoiding civilian casualties may be a military advantage. Therefore, the SOTF commander may view the death of the civilian hitchhiker not just as collateral damage but as negatively impacting the anticipated military advantage of the attack on the HVI.

Conclusion

While this post identifies several factors a commander may consider when assessing the military advantage of an attack, it is not exhaustive. Commanders may draw on a wide range of considerations throughout the targeting process, and their evaluation of military advantage is both iterative and dynamic. Commanders and command staff must consistently monitor battlefield conditions, reassess operational plans and targeting decisions, and adapt to shifting objectives and enemy actions while minimizing collateral damage. Given the inherent complexity and fluidity of combat, commanders should tailor the evaluation of the military advantage to the contexts and specifics of each attack.

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Lieutenant Colonel Kevin S. Coble is an active-duty Army judge advocate and the Deputy Staff Judge Advocate for the 10th Mountain Division (Light Infantry) at Fort Drum, New York.

The views expressed are those of the author and do not necessarily reflect the views or official position of the United States Military Academy, Department of the Army, Department of Defense or its components. 

Articles of War is a forum for professionals to share opinions and cultivate ideas. Articles of War does not screen articles to fit a particular editorial agenda, nor endorse or advocate material that is published. Authorship does not indicate affiliation with Articles of War, the Lieber Institute, or the United States Military Academy West Point.

 

 

 

 

 

Photo credit: Airman 1st Class William Rio Rosado