Mechanisms of Coercion: Strategic Bombing Lessons for Economic Sanctions
By Astor Lu
When Russian troops rolled into Ukraine in late February, economic sanctions quickly emerged as the U.S.’ retaliatory weapon of choice. On the surface, they appear to be a Goldilocks-esque option for President Biden and his administration — more punch than rhetoric and diplomacy, yet short of military intervention. The heart of the American response to the invasion is coercion: how can the U.S. and its allies compel Vladimir Putin to cease military operations in Ukraine? The answer may appear in the war-torn skies of eighty years ago. While the two may initially appear unrelated, the history of strategic bombing offers much-needed guidance on sanctions. Fundamentally, both have been misused. Rather than making sanctions the centerpiece of a coercive strategy, leaders should incorporate them as valuable but supporting components in a larger plan.
The use of coercive tools can be categorized into two groups: decisive and subordinate. The former entails using the tool as the main thrust, the action that is pivotal in achieving the desired effect. Clausewitz would describe it as a friendly “center of gravity.” In a mission to level an enemy city, for example, the decisive piece would be the bomber carrying the nuclear weapon. Other factors — fighter escort, command-and-control aircraft, and diversionary raids included — would be merely supporting. Those secondary tools are the subordinate group. They may be helpful or necessary to achieving the objective, but they are not the centerpiece of the effort. The effects-based nature of coercion is important; in Ukraine, military and political compromise by the Russians is the one and only indicator of success for Western compellence policies. The U.S. could wipe out 99% of Russia’s economy with sanctions and make a ruble worth a grain of sand, but if Putin did not withdraw from Ukraine the sanctions program would be considered a failure.
Similar to economic sanctions, strategic bombing appeared to be a relatively humane way of resolving conflicts during its early development after the First World War. Over the interwar years, theorists came to believe that strategic airpower could win wars alone. Airpower prophets such as Giulio Douhet, Billy Mitchell, and Hugh Trenchard spread the view that bombers could independently cause such pain to an enemy population — whether by directly striking them, starving them, or hurting their economy — that they would force their governments to sue for peace. More generally, the theorists believed that states could coerce enemy powers politically and militarily by applying pressure to their populace.
Those theories failed during the Second World War because airpower had little value as a decisive tool of coercion. Initially, American air planners believed that targeting certain nodes in German industry would collapse the economy. They targeted ball bearings and the electrical grid, for example, which were economically necessary, geographically concentrated, and vulnerable to disruption. The Germans responded by simply redistributing the stress to other sectors. “Morale bombing” of urban areas, meanwhile, failed to compel the Japanese to surrender. The specific reasons for their capitulation are disputed, but the decisive factor was certainly not popular pressure from U.S. firebombing. A cursory glance at a history textbook would show that neither economic breakdown nor mass protests ended the war in Europe or the Pacific.
Airpower was effective as a subordinate tool, though. The air campaign against German oil, for example, was hugely successful. When the Germans launched the Ardennes offensive in 1944, the Army High Command Quartiermeister had only twelve million liters of fuel, or three days’ supply. During their retreat, the commander of the Sixth SS Panzer Army left behind 180 tanks due to lack of fuel. Strategic bombing also ground down the Luftwaffe by forcing them into the air to fight. When Allied troops landed in Europe, one German general compared the resulting air superiority to being a chess player who could move once for every three moves by his opponent. Altogether, World War II airpower was strategically ineffective when deployed alone, but rewarding when used in a supporting role to a broader, ground-centric strategy.
What relevance does airpower in 1944 have for sanctions in 2022? Both strategies are intended to compel the enemy to change its behavior by indiscriminately causing pain to the population. The only difference is that the incendiary bombs of 1944 are the export controls and asset seizures of today. For both, the specific mechanism of how pressure on the populace translates to changes in policy is unclear and possibly nonexistent. Also, just like strategic bombing, sanctions have a weak historical record. Out of 105 cases between 1914-1990, according to political scientist Robert Pape, only five cases clearly demonstrate successful use of sanctions in political compellence. Yet airpower, despite originally being intended to be the decisive factor in the war, ultimately found success as a supporting function to a ground war. Perhaps sanctions could do the same.
On future policy, decision-makers must establish that using economic sanctions as they are currently being used — as a decisive tool of coercion — will likely be unsuccessful and merely demonstrative. In the case of Ukraine, they will probably not convince Putin to withdraw or make concessions. The West must use sanctions as a subordinate tool in a larger strategy oriented around a different “center of gravity”: making it difficult to fund or supply the Russian war machine, for example.
Naturally, the decision on whether to use sanctions is more nuanced than solely the question of their effectiveness. World leaders who want neither to sit on their hands (or appear to do so) nor send their citizens home in body bags often choose sanctions because it feels and looks like they are taking real action. Moreover, the fact that sanctions incur costs to the imposer demonstrates more commitment than sending “thoughts and prayers.” Above all, President Biden must weigh the costs and benefits of defending Ukraine with an accurate image of sanctions in his mind: that they cannot be relied upon to produce coercive gains on their own, just like strategic bombers could not be relied upon to independently rid the world of Nazi Germany and Imperial Japan. Whether that conclusion equals the need for further action is a separate conversation. But policymakers must not trick themselves into thinking that placebos cure diseases. Unfortunately, they do not.