Cyber Crucible

"In This Thing with Both Feet": Eisenhower and Operation Overlord's Airpower

Joe R. Bailey

This is a reprint of Chapter 1 from Lethal and Non-Lethal Fires: Historical Case Studies of Converging Cross-Domain Fires in Large-Scale Combat Operations, part of The Large-Scale Combat Operations Series.


Multi-Domain Battle requires the ability to maneuver and deliver effects across all domains in order to develop and exploit battlefield opportunities across a much larger operational framework. It must include whole-of-government approaches and solutions to military problems and address the use of multinational partner capabilities and capacities.1

- General David Perkins, Commanding General, US Army Training and Doctrine Command


In January 1944, General Dwight Eisenhower assumed his new post as Supreme Commander of the Allied Expeditionary Force in Europe, the headquarters responsible for the cross-channel invasion of continental Europe, also known as Operation Overlord. Among the many problems Eisenhower encountered was the necessity of making airpower an asset for the coming invasion. This consumed enormous amounts of his time, particularly his effort to gain operational control of American and British strategic bombers.

As the Army implements multi-domain operations into its doctrine, leaders should look to the ways in which Eisenhower skillfully maneuvered these choppy winds and made airpower a viable cross-domain fire that directly supported the cross-channel invasion. To achieve this, the new Supreme Commander fought to establish effective command arrangements and organization for the use of airpower. He not only overcame parochial and competing interests between different services but did so while establishing a complex, multi-national command. Eisenhower also negotiated a complex web of organizational, political, and ethical problems as the air support plan unfolded.

Eisenhower knew that airpower would be a decisive component in the coming invasion. The first step in making it effective meant ensuring unity of command and bringing all air forces under his strategic and operational direction. In keeping with his background as an infantry officer, Eisenhower had concluded that Germany would ultimately have to be defeated on the ground. Thus, he argued that strategic bombers should directly support Overlord's ground forces for a limited period before and after the invasion. He disagreed with strategic bombing advocates who argued the primary mission of airpower was to destroy Germany's economic centers and defeat the military capacity of Germany to fight. He also disagreed that their use of strategic bombing would render an invasion of Europe unnecessary.2

Eisenhower clearly saw the joint nature of airpower. Although he believed that the first mission of airpower was support of ground troops, he never opposed the strategic bombing of Germany. To his thinking, strategic airpower could weaken Germany and achieve air superiority for his Allied ground forces. Time and again, however, Eisenhower called on strategic bombers for operational missions that diverted them from bombing Germany. In giving strategic bombers operational missions directly supporting the invasion, Eisenhower established that support of ground forces took precedence over the strategic bombing of Germany.

After the war, Eisenhower explained his belief in the dual role of airpower. He noted:

Many ground soldiers belittled the potentialities of the airplane against ground formations. Curiously enough, quite a number of Air Force officers were also antagonistic to the idea, thinking they saw an attempt to shackle the air to the ground and therefore a failure to realize the full capabilities of air attack. It was patiently explained over and over again that, on the contrary, the results of coordination would constantly advance the air bases and would articulate strategic bombing effects with ground strategy, so that as the air constantly assisted the advance of the ground forces its long-range work would not only be facilitated but destruction of its selected targets would contribute more effectively and directly to Nazi defeat.3

Eisenhower and the Challenges of Unity of Command

Eisenhower's problems with airpower organization and command structures that threatened unity of command began even before he assumed his position as Supreme Commander of the Allied Expeditionary Force. In 1943, British planners for Overlord urged the Combined Chiefs of Staff to decide the organization of tactical airpower for the invasion. In a message to Army Chief of Staff George C. Marshall on 31 December 1943, Eisenhower bitterly complained about those arrangements. He pleaded with Marshall, "I most earnestly request that you throw your full weight into opposing the tendency to organize in advance the sub-echelons of the Overlord operation in such a way as to tie the hands of the command and Allied staff." Eisenhower also noted that he and many of his staff had learned the dangers of such arrangements during his tenure as Allied commander during Operation Torch in North Africa, and he urged the Army Chief of Staff to let him apply that experience to Overlord's organization.4

As he became familiar with the organization of the command he was about to assume, Eisenhower also found that Air Chief Marshal Arthur Tedder, a Royal Air Force officer with vast experience in the Mediterranean, had been assigned as his Deputy Supreme Commander, although this officer came "without portfolio [without definite responsibilities]." On the other hand, Air Chief Marshal Trafford Leigh-Mallory was given command of the tactical air forces although he styled himself as commander of all air forces for Overlord. These arrangements and divided authority troubled the Supreme Commander deeply. Eisenhower's Chief of Staff, General Walter B. Smith, told him, "I personally believe that Tedder should be the real air commander and your advisor on air matters, which Mallory now considers himself. I don't think there is a place for both of them." Before assuming command in England, Eisenhower took a short leave back to the United States. After a few days of travel with his wife, Eisenhower arrived in Washington to meet with Marshall and Chief of Staff for the Army Air Forces, General Henry "Hap" Arnold. Eisenhower continued his protest of the air arrangements proposed by the Combined Chiefs of Staff and also voiced his displeasure at the controversy over Leigh-Mallory and Tedder.5

At the same meeting the new Supreme Commander argued that both American and British strategic bombing commands should come under his operational control for the invasion. Commanders of both strategic bombing forces, Air Chief Marshal Arthur Harris and General Carl Spaatz, however, wanted to continue their strategic bombing of Germany, insisting that this more effectively employed the bombers. Eisenhower referred to their opinions as "dangerous nonsense" and insisted that the most effective use of strategic air forces was to directly support Overlord.6 Eisenhower left Washington for his new command without a satisfactory solution to his airpower problems. The topic received much attention and debate over the next several months.

One of the many insights that Eisenhower gleaned from his time as the Allied commander in the Mediterranean regarding airpower came from the landing at Salerno. This bloody affair, where Allied forces landed on the Italian Peninsula and established a beachhead, cemented within the Supreme Commander's mind that soldiers on the ground needed responsive airpower at critical times. This experience shaped his future view of airpower organization for Overlord. Eisenhower later stated, "My insistence upon commanding these air forces at the time was further influenced by the lesson so conclusively demonstrated at Salerno: when a battle needs the last ounce of available force, the commander must not be in the position of depending upon request and negotiation to get it." He added, "It was vital that the entire sum of our assault power, including the two Strategic Air Forces, be available for use during the critical stages of the attack."7

Very early, Eisenhower attempted to achieve some consensus on the consolidation of airpower for Overlord. In fact, the Supreme Commander began this implementation before he left Washington to take his new command. Trying to bring the American and British strategic bomber commands under his operational control consumed much of his time. On 5 January 1944, he sent a message to Smith anticipating difficulty in making the necessary arrangements to integrate the tactical and strategic air forces according to his plan. He told Smith that Tedder should be sent to consult with Spaatz, head of US Strategic Air Forces, to begin planning for this integration. Eisenhower was already directing Tedder, his deputy commander without portfolio, in matters concerning airpower.8

On the same day, Lt. Gen. Thomas Handy, the Army's Chief of Staff for Operations, sent a message to Spaatz telling him that the Supreme Commander saw his strategic bombers and those of Air Chief Marshal Harris, his British counterpart, as the "big guns" for Overlord. Through Handy, Eisenhower asked Spaatz to operate in conjunction with Harris and his British Bomber Command. Eisenhower had also noted, "While the above conception has not been officially approved by all concerned, it offers the only chance of success, and therefore I am confident will be accepted by everyone shortly."9 Nothing, however, could have been further from the truth. Argument through diplomatic and military channels over airpower concerns continued for several months. This proved to be only the first in a long series of debates that emerged about the use and control of airpower in support of Overlord.

The Supreme Commander, while uncompromising in his requirements for Overlord's airpower needs, was willing to negotiate in order to achieve acceptance of his plan by the Americans and the British. In a message to Arnold, Eisenhower stated, "To get what I want, I am perfectly willing to avoid terms and language that may startle anyone. But there can be no evasion of the certainty that when the time comes, the Overlord Commander must have the full power to determine missions and priorities for all forces." Eisenhower anticipated little trouble from British Prime Minister Winston Churchill but was prepared to present his case to the Combined Chiefs of Staff, if necessary.10

The Air Plan to Support Overlord

Eisenhower directed his staff, under the leadership of Tedder, to begin a plan that could be presented to the Combined Chiefs of Staff. On 9 February 1944, Eisenhower told Marshall that the air plan would be completed in the next few days. He stated, "This plan will not only lay out exactly what we have to do, with our priorities, but will also fix our recommended dates for the passage of command over Strategical Air Forces to this Headquarters. Before I present it to the Combined Chiefs of Staff, I am going to have a Commanders-in-Chief meeting on it so that thereafter it becomes 'doctrine' so far as this Headquarters is concerned."11

Eisenhower's desire to bring American and British strategic bomber forces under his operational control during Overlord brought many objections from, not only the British government, but also from the strategic commanders Spaatz and Harris. One objection that British and American air commanders had was the appointment of Leigh-Mallory as the Commander in Chief for Air of the Allied Expeditionary Force. Both Spaatz and Harris remained reluctant to take orders from Leigh-Mallory, a commander whose experience was with tactical air forces and not strategic bombers. Eisenhower also experienced objections from Prime Minister Churchill.12 During this debate, Eisenhower told Marshall, "The Prime Minister was quite violent in his objections to considering Leigh-Mallory as the overall Air Commander-in-Chief, although this was his definite assignment."13

In order to gain Churchill's approval and that of the Combined Chiefs of Staff, Eisenhower was willing to negotiate on parts of the air plan, but stood fast and refused to consent to losing operational control of the Allied strategic bomber commands. On 29 February 1944, Eisenhower told Tedder about Churchill's objections to Leigh-Mallory's command of the strategic bombers and urged Tedder to find solutions with Spaatz and Harris. If a solution could not be found, he warned, "the P. M. [Prime Minister] will be in this thing with both feet." He explained his conceptual basis for operational control and told Tedder, "I'm quite prepared, if necessary, to issue an order saying I will exert direct supervision of all air forces - through you - and authorizing you to use headquarters facilities now existing to make your control effective. L. M.'s [Leigh-Mallory's] position would not be changed so far as assigned forces are concerned but those attached for definite periods or definite jobs would not come under his command."14

On 9 March 1944, Eisenhower solved some of these problems with airpower organization. A new directive gave Tedder overall command of the air forces for the invasion. Eisenhower would exercise control of these air forces through Tedder; Leigh-Mallory would command the tactical air forces that consisted of the US Ninth Air Force and the British Second Tactical Air Force. General Spaatz and Air Chief Marshal Harris directed their respective strategic bombing units under Tedder's supervision. The turnover of Spaatz's and Harris's bombers to Eisenhower's operational control would take place after the Supreme Commander and British Air Chief of Staff, Air Chief Marshal Charles Portal, agreed on an overall air plan for their use in Overlord. Eisenhower sent a message to Marshall telling him, "This morning it appears to me the air problems are at last in good order and will be presented officially to the Combined Chiefs of Staff quickly. All air forces here will be under Tedder's supervision as my agent, and this prospect is particularly pleasing to Spaatz." The Supreme Commander also messaged Arnold, "I think we have our Air Forces pretty well straightened out. As you can well imagine it has not been simple because of the independent status that so many of these Air Forces have heretofore enjoyed."15

Feeling confident that his plans were moving forward, Eisenhower was surprised a week later when the British raised objections to the wording in the agreement with the Combined Chiefs of Staff regarding his control of the strategic bombing forces. Eisenhower's frustration was evident when he observed that, "the air problem has been one requiring a great deal of patience and negotiation." He recorded in his diary: "In the messages coming back and forth from Washington, a sudden argument developed over the use of the word 'command.' The whole matter I had considered settled a week ago, after many weeks of argument. This did not seem important at the time the drafts were first drawn up, but as long as the question was raised I have recommended to General Marshall that a word be adopted that leaves no doubt in anybody's mind of my authority and responsibility for controlling air operations of all three of these forces during the critical period of Overlord."16 The Supreme Commander made it clear that he would have the ability to give strategic bombers tactical missions in support of Overlord, or he would quit. Eisenhower was insuring that all military assets under his command would work to further the objectives of the all-important invasion.

Eisenhower Threatens to Resign

Growing increasingly frustrated by the constant bickering of those objecting to his airpower plan, Eisenhower determined to wrestle control of the strategic bombers or to go home. He noted that he would have one more meeting with his air commanders to attempt implementation of his plan and wrote, "If a satisfactory answer is not reached, I am going to take drastic action and inform the Combined Chiefs of Staff that unless the matter is settled at once I will request relief from this command." On 6 March 1944, General George Patton walked into Eisenhower's office in the middle of a telephone conversation between Tedder and the Supreme Commander. Patton arrived in time to hear Eisenhower say, "Now, listen, Arthur, I am tired of dealing with a lot of prima donnas. By God, you tell that bunch that if they can't get together and stop quarreling like children, I will tell the Prime Minister to get someone else to run this damn war. I'll quit." Eisenhower also told Churchill that if he did not receive a total commitment of the bombers that he would "simply have to go home."17

Evidently Eisenhower's threats to resign did not fall on deaf ears. Churchill, eventually, agreed to the Supreme Commander's arrangement to exercise operational control of the strategic bombers. After being informed of wording problems associated with his "command" of the strategic bombers and noting that he would resign short of a satisfactory solution, later that day Eisenhower added a postscript to his diary stating that the chiefs-of-staff found the word "direction" acceptable, and he expressed relief.18


Although Eisenhower won operational control of the strategic bombing commands under Spaatz and Harris, the Supreme Commander still experienced trouble attempting to perfect the new organization. Many British and American authorities remained confused about who would actually give the strategic bombers their instructions. They also remained confused about when Eisenhower's direction of the bombers would begin. On 12 April 1944, he wrote Marshall telling him, "For the past two weeks all air operations have been under my general direction and although it takes a little time to get new operational lines completely sorted out where there have been so many independent voices and authorities, everything in that particular field is working satisfactorily."19

The problems associated with organizing his air plan remained on Eisenhower's mind for several months. On 22 May 1944, he mentioned these problems in his diary. He complained, "One of our most difficult problems here has been the setting up of a completely satisfactory air organization. This comes about because of the widely scattered interest of the air forces and the great strength of units that have been acting in almost an independent way. However, somewhere about 10 April, a special arrangement was worked out that gives the supreme commander all the authority necessary to secure full support from all the air forces in England."20

While fighting to gain operational control of the strategic bombers, the Supreme Commander faced a concurrent argument about how to best employ strategic airpower to support the invasion once the bombers were under his direction. Initially, Eisenhower believed that the invasion's success hinged on Allied air superiority. In his postwar report as Supreme Commander of the Allied Expeditionary Force, Eisenhower declared, "The Strategic Air Forces also would be given definite tactical responsibilities during critical periods [in preparing for the invasion], although their principal mission would be to continue their attacks on the industrial potential of Germany, with emphasis now placed on the facilities for aircraft production. They had also definite tactical responsibilities at critical periods of the battles."21 Eisenhower told Marshall that the Strategic Air Forces of Spaatz were taking every opportunity to "force the Luftwaffe to fight, and noted that Spaatz's operations were "taking a big toll of the enemy."22

To Eisenhower, Allied air superiority was vital to Overlord's success. Air superiority allowed freedom of action that enabled the stockpiling of men and equipment in England essential to the invasion. Secondly, establishing a firm beachhead in France necessitated the Luftwaffe be weakened to the point that they could not oppose the Allied landings. The Supreme Commander recalled, "Quite apart from the direct assistance these attacks lent to the success of our landings, they were essential also as a preliminary to the intensive bombing of German industry." Eisenhower once again exhibited that he supported strategic missions so far as they assisted in the conduct of Overlord, but one could not mistake that the invasion was his priority for the use of strategic airpower.23

The Transportation Plan

Having largely achieved air superiority during Big Week, when the strategic air forces forced the Luftwaffe to fight and incur damaging losses in planes and pilots, Eisenhower focused on ways to more effectively employ airpower as part of the invasion. In his postwar report on operations of the Allied Expeditionary Force, the Supreme Commander conveyed his intent. He recalled, "Until January 1944, the view had been held that the heavy bombers of the Strategic Air Forces could make sufficient direct contribution to the assault in a period of about a fortnight before D-day. Further consideration, however, indicated the need to employ them for a much longer period - about three months - and a plan was finally adopted which aimed at the crippling of the French and Belgian railway systems and the consequent restriction of the enemy's mobility." This plan became known as the Transportation Plan, and it called for a large role to be played by both the tactical and strategic air forces.24

The Transportation Plan intended to deprive the Germans of the ability to concentrate troops rapidly in the invasion area. To do this, the Transportation Plan called for attacks by the tactical air forces against railroads, bridges, and communications centers beginning two months before the invasion. The Supreme Commander ultimately hoped that the plan would "hinder his [German] efforts to maintain an adequate flow of reinforcements and supplies, forcing him to move by road with resultant delay, increased wastage in road transport and fuel, and increased vulnerability to air attack." In order to conceal the actual place of the invasion, however, Eisenhower's planners had to avoid concentrating all of their attacks on the invasion area. Instead, they attacked targets in a wide area and, shortly before D-Day, they began concentrating their attacks on areas vital to Overlord.25

The Transportation Plan enjoyed support from Tedder, Leigh-Mallory, and most of the ground commanders. Like much of his entire air plan, however, Eisenhower's Transportation Plan encountered resistance. Among those objecting to the plan were the commanders of the American and British strategic bombing forces, Prime Minister Winston Churchill, and the British War Cabinet. Allied predictions of the Transportation Plan noted that it would kill 10,000 to 15,000 French citizens if implemented. Churchill and the War Cabinet, considering the possible political ramification for postwar France, balked at this idea and urged Eisenhower to develop another plan. Churchill recommended that the air forces should engage "bases, troop concentrations, and dumps." On 29 April 1944, Eisenhower told Marshall that Churchill's recommendations were simply not practical. He noted, "The fact is that any large dumps are obviously located near marshaling yards while troop concentrations are by battalion in little villages. Any immediate attempt to bomb the German troop units throughout France would probably kill four Frenchmen for every German." The Supreme Commander also noted that there was simply no other way the Allied Air Forces could help him in the period before Overlord commenced. Eisenhower argued for the necessity of the Transportation Plan.26

Eisenhower had previously told Churchill something very similar on 5 April. He remarked, "After long study by our transportation experts as well as by our senor airmen, it was decided that the only preparatory field in which our air force could be profitably employed, other than its normal task of destroying the hostile air force, was against the enemy's transportation system." The Supreme Commander also told Churchill that he simply did not see any other way of effectively using airpower to aid Overlord, and noted that he thought the estimates of French casualties were "grossly exaggerated."27

Eisenhower continued this discussion with Churchill on 2 May 1944. He told the Prime Minister that he had taken steps to reduce French civilian casualties during the conduct of the Transportation Plan. These steps included issuing warnings to the population before attacks occurred and waiting to attack large rail centers in close proximity to large civilian populations at the latest possible date. Eisenhower did, however, indicate that civilian casualties were inevitable in any operation using airpower and once again noted that the estimates of French lives that would be lost were likely overstated. On the other hand, Eisenhower argued that the bombing of rail centers would inflict very heavy casualties upon French railroad personnel. Finally, Eisenhower told Churchill that he had consulted with his staff and found no alternative to implementing the Transportation Plan, writing that he appreciated "the gravity of the issues raised," but stated, "The 'Overlord' concept was based on the assumption that our overwhelming air power would be able to prepare the way for the assault. If its hands are to be tied, the perils of an already hazardous undertaking will be greatly enhanced."28 He explained to the Prime Minister in no uncertain terms that he understood the political ramifications in a postwar world between France and the Allies if bombing killed large numbers of French civilians. Eisenhower argued, however, that the Transportation Plan was a vital component to the success of Overlord and must proceed regardless of the casualties it inflicted on the French civilians.

While the British War Cabinet and Prime Minister opposed the Transportation Plan because of the projected casualties to French civilians and the fear of resulting political ramifications, the Allied strategic air force commanders opposed the plan for other reasons. They thought that the strategic bombing campaign against Germany was of vital importance, and that it should not be discontinued for the more tactical role of preparing the French coastal areas for the invasion. Most strategic bombing advocates argued that the continuation of Operation Pointblank, the strategic air assault against Germany, would render the invasion of Normandy unnecessary.


In early February 1944, General Carl Spaatz, commanding American strategic forces in Europe, and Air Chief Marshal Arthur Harris of Royal Air Force (RAF) Bomber Command objected to the Transportation Plan. Spaatz believed that targets under the Transportation Plan were of little value and jeopardized achieving air superiority before the invasion. Harris wanted to continue the area bombing of German cities. General James Doolittle, commanding the Eighth Air Force later noted that he thought "the Strategic Air Forces could render more effective aid to the war effort by denying the enemy the facilities he required than by giving direct support to our ground forces." In other words, Doolittle thought that the continued strategic bombing of Germany was more effective than using strategic bombers as part of Eisenhower's Transportation Plan.29

Eisenhower consistently attempted to convince strategic bombing advocates that he did not want to discontinue Operation Pointblank. The Supreme Commander had viewed the continued strategic bombing operations as a way of gaining air superiority by forcing the Luftwaffe to fight. Now that Eisenhower had gained the desired control of the air, he argued that strategic bombers would be most useful in helping achieve the goals of the Transportation Plan although he never wished to completely abandon Pointblank. During his fight to secure control of the strategic bombers, he told Tedder, "It is equally important that the plan recognize the tremendous advantages accruing to Overlord through current Pointblank operations and therefore be so developed that from the very beginning the air operations of Pointblank and Overlord are completely integrated."30

Nevertheless, the objections by Spaatz and Harris continued. Before D-Day, Harris warned Eisenhower that a temporary stop of the strategic bombing to assist the invasion would allow Germany, within five months, to fully restore its war production.31 Although Eisenhower made the decision to use strategic bombers as part of the Transportation Plan, he demonstrated again that he recognized the significance of Pointblank. In May 1944, he wrote Harris noting, "I have of course been familiar with the over-all strategic effort against Germany from the air, but since you showed me last night the photographs and charts portraying the extensive damage inflicted upon the enemy within the boundaries of his own country, I am more impressed than ever."32 After the invasion gained a foothold, Harris reminded the Supreme Commander of his warning and urged that the Allies return to the strategic bombing of Germany as soon as possible. Eisenhower told the British air commander, "I hope I have never left any doubt as to my desire to return all the Strategic Air Forces to the bombing of Germany to the greatest extent at the earliest possible moment. I have been quite pleased, lately, to note the extent which Bomber Command and the Eighth and Fifteenth Air Forces have been hitting the centers of German production. Of course we always have the emergencies of the battle front, and, most of all, the necessity for beating down Crossbow."33

Counter to the Transportation Plan: The Oil Plan

In March 1944, General Spaatz briefed a plan he thought was more effective than the Transportation Plan. Spaatz's alternative became known as the Oil Plan because it called for the destruction of Germany's oil production facilities and redefined Pointblank operational priorities. Spaatz argued that the Transportation Plan was not viable. In short, he believed that the plan included too many targets, and it would take too long to see any noticeable effects. The Oil Plan, however, would only require fifteen days of visual bombing for the 8th Air Force and 10 by the 15th Air Force to reduce the German oil production to 80 percent. Advocates of the Transportation Plan, however, argued that the effects of the Oil Plan would not be timely enough to support the invasion. Tedder wrote after the war, "It was considered that, since the enemy would almost certainly be holding ample stocks of oil in France to meet the immediate emergency, attack on the oil industry was not likely to give the immediate assistance which the assault required. It was therefore decided that the primary target system for the Allied strategic bomber forces should be the transportation system upon which the movements of enemy reinforcements would depend."34 After protracted debate, Eisenhower settled on the Transportation Plan. Now, with his airpower plan complete, the strategic bombers came under his operational control and Ike settled his command arrangements with his air commanders.

Airpower over Normandy

On 6 June 1944, Operation Overlord commenced, and both strategic and tactical air forces saw large-scale use. On that day alone, 8th Air Force and RAF Bomber Command flew 5,309 sorties and dropped 10,395 tons of bombs. The tactical air forces flew 5,276 sorties. Targets on D-Day remained largely confined to enemy troop concentrations, defensive works, gun positions, and communications centers.35

Eisenhower and his staff continued contemplating the role of airpower after a lodgment was established. On 3 June 1944, Eisenhower wrote that he envisioned offensive operations moving forward in two distinct zones of advance, one British and the other American. At that time, he planned the establishment of a second army group commanded by General Omar Bradley, which would pursue this strategy. The Supreme Commander wanted each one of the groups to be supported by its own contingent of fighters and fighter-bombers. Eisenhower stated, "At that time a certain portion of the so-called 'tactical' air force, that is, medium bombers and possibly some of the long-range fighters, will remain under the commander in chief, AEF (Allied Expeditionary Force). This portion of the tactical air force will be available to assist either army group."36

Eisenhower's vision for a second army group came to fruition after the invasion gained a stable beachhead. In addition to the tactical air forces that supported each army group, Eisenhower continued using strategic bombers to support the ground campaign. Eisenhower wrote, "In addition to the strategic bombing of oil, aircraft, and communications targets, we were, during the campaign, to call upon the Strategic Air Forces for tactical support. At the time of the breakthrough in Normandy . . . strategic bombers were employed in strength to attack enemy positions, supply bases immediately supporting the enemy front, and strongpoints and communication centers within the battle area. In these instances of tactical assistance, the Strategic Air Forces aided immeasurably in turning the decision of battle in our favor."37

One of Eisenhower's more effective uses of airpower after the landings was its use in breaking up enemy troop concentrations. Before the invasion, he noted in a memorandum, "Because the enemy in great strength is occupying a country that is interlaced with a fine communication system, our attack can be looked upon as reasonable only if our tremendous air force is able to impede his concentrations against us and to help destroy the effectiveness of any of his counterattacks." Five days later, after Allied troops had landed on the Normandy beaches, Eisenhower noted that the situation was fluid and that added to the difficulty of assigning targets to air assets. He was, however "confident that if weather permits our air will intervene effectively in any attempted counter attacks by the enemy."38

Although tactical aircraft engaged enemy troops, equipment, and transportation, the Allied strategic bombers did not receive another substantial mission until the commencement of Operation Goodwood, an offensive operation planned in the British sector of Normandy. On 18 July 1944, approximately 1,700 bombers from RAF Bomber Command and the 8th Air Force, in addition to other bombers belonging to the 9th Air Force, dropped 8,000 tons of bombs in advance of ground operations. In this operation, commanders learned from previous experience and avoided cratering the ground that ground forces would need to cross by only using fighter bombers in attack lanes established for armored divisions. They also ordered ground units to "attack immediately after the air strike in order to capitalize on the paralyzing effect of the bombardment on the Germans."39


Operation Cobra, a breakout attempt in the American sector, included plans for massive air support preceding the offensive. The planners arranged target areas and bombing durations for the various types of participating bombers, timetables for the withdrawal of American soldiers to a zone of safety, and made arrangements to mark the target areas for the aircraft. Tragically, despite the elaborate planning, the situation went awry almost immediately. On 24 July, the day the attack was to commence, Air Chief Marshal Leigh-Mallory was on the ground to observe it. Realizing that the sky was too overcast for the planned air support, Leigh-Mallory attempted to call the bombardment off but could not reach all of his aircraft. Some bombers reached their targets and subsequent accidents and miscalculations resulted in dropping bombs on positions occupied by American infantrymen.40

Commanders halted the operation until the next day. Another bombardment commenced on 25 July 1944. Formations of heavy, medium, and fighter bombers dropped more than 4,150 tons of bombs in support of Operation Cobra. Despite further planning to prevent such occurrences, again, poor weather conditions and human error resulted in short drops that killed 111 American soldiers and wounded another 490. Among the dead was Lt. Gen. Lesley McNair, commander of Army Ground Forces. Eisenhower subsequently told Bradley that he would never again use heavy bombers in support of ground forces, but later changed his mind.41

Referring later to Goodwood, Eisenhower remarked, "Although only temporary in effect, the results of the bombing were decisive so far as the initial ground attack was concerned. Actual casualties to the enemy, in his foxholes, were comparatively few, but he was stunned by the weight of the bombing and a degree of confusion was caused which rendered the opposition to our advance negligible for some hours." He also noted, "At the same time, the spectacle of our mighty air fleets roaring in over their heads to attack had a most heartening effect upon our own men." The Supreme Commander said similar things about airpower in support of Cobra. While the bombardments did not inflict large numbers of German casualties, "the bewilderment of the enemy was such that some men unwittingly ran toward our lines and four uninjured tanks put up white flags before any ground attack was launched." The Supreme Commander also lauded the success of airpower in other ways. He stated, "The closeness of the air support given in this operation, thanks to our recent experiences, was such as we should never have dared to attempt a year before. We had indeed made enormous strides forward in this respect." He added that "from the two Caen operations we had learned the need for a quicker ground follow-up on the conclusion of the bombing, for the avoidance of cratering, and for attacks upon a wider range of targets to the rear and on the flanks of the main bombardment area." Despite the setbacks, airpower proved valuable in these operations.42


Eisenhower faced similar challenges in organizing and coordinating airpower on the eve of the Normandy invasion in 1944. As today's commanders work to implement cross-domain fires, they would do well to study Eisenhower's airpower accomplishments in support of Overlord.

Airpower served as a valuable, albeit imperfect, cross-domain fire in the period before, during, and after Overlord. Although critical to the invasion, the effectiveness and success of airpower in Normandy was not inevitable. On the contrary, Eisenhower, in his role as Supreme Commander, engineered the attainment of effective airpower. Through the force of his personality and experience, Eisenhower achieved unity of command for airpower operations supporting Overlord and created an organization ensuring that all components worked toward the same goal. Additionally, Eisenhower overcame inner and inter-service rivalries, differing international priorities, and political challenges while deftly and diplomatically orchestrating his own version of multi-domain battle. Today's commanders face similar challenges while establishing cross-domain fires, in addition to establishing multi-domain organizational frameworks. For example, Field Manual (FM) 3-0, Operations, refers to the responsibilities of a theater army commander, noting, "These forces are either allocated or assigned to the combatant commander, who establishes command and support relationships with the theater army as required." FM 3-0 also addresses the role of coordinating cross-domain fires. According to the manual, "Commanders ensure the coordinated use of indirect fires, AMD, and joint fires to create window of opportunity for maneuver and put the enemy in a position of disadvantage. This is accomplished through the operations process, fire support planning, and targeting. . . . Commanders use long-range fires (rocket, naval, surface fire support, and rotary and fixed-wing air support) to engage the enemy throughout the depth of their AO [Area of Operations]."43





  1. US Army Capabilities Integration Center, "Multi-Domain Battle: Evolution of Combined Arms for the 21st Century, 2025-2040," December 2017.
  2. Stephen Ambrose, Eisenhower: Soldier and President (New York: Simon and Schuster, 1990), 121. Lt. Col. Michael J. Finnegan also addressed Eisenhower's effort to achieve unity of command in "General Eisenhower's Battle for Control of the Strategic Bombers in Support of Operation Overlord: A Case Study in Unity of Command" (US Army War College, 1999).
  3. Dwight Eisenhower, Crusade in Europe (New York: Doubleday and Company, 1955), 47.
  4. isenhower to General George Marshall, 31 December 1943, Alfred D. Chandler, ed., The Papers of Dwight David Eisenhower, The War Years 3 (Baltimore: Johns Hopkins University Press, 1970), 1648-49.
  5. Walter Bedell Smith to Eisenhower, 30 December 1943, The Eisenhower Papers, 1648, n. 1.
  6. Ambrose, Eisenhower: Soldier and President, 121.
  7. Eisenhower, Crusade in Europe, 221-22.
  8. Eisenhower to Smith, 5 January 1944, The Eisenhower Papers, 1651.
  9. General Thomas T. Handy to General Carl Spaatz, 5 January 1944, The Eisenhower Papers, 1654.
  10. Eisenhower to Henry Arnold, 23 January 1944, The Eisenhower Papers, 1677.
  11. Eisenhower to Marshall, 9 February 1944, The Eisenhower Papers, 1715.
  12. Eisenhower to Tedder, 29 February 1944, The Eisenhower Papers, 1755-56; Arthur Tedder, With Prejudice (Boston: Little, Brown and Company, 1966), 508-12; and The Eisenhower Papers, 1756, n. 1.
  13. Eisenhower to Marshall, 3 March 1944, The Eisenhower Papers, 1758.
  14. Eisenhower to Tedder, 29 February 1944, The Eisenhower Papers, 1755-56.
  15. Dwight Eisenhower, Report of the Supreme Commander to the Combined Chiefs of Staff on the Operations in Europe of the Allied Expeditionary Force 6 June 1944-8 May 1945 (Washington, DC: US Army Center of Military History, 1994), 9-10; Eisenhower Memorandum, 22 March 1944, The Eisenhower Papers, 1784; Eisenhower to Marshall, 10 March 1944, The Eisenhower Papers, 1766-67; and Eisenhower to Arnold, 15 March 1944, The Eisenhower Papers, 1768.
  16. Eisenhower Memorandum, 22 March 1944, The Eisenhower Papers, 1784-85.
  17. Eisenhower Memorandum, 1785; Ambrose, Eisenhower: Soldier and President, 126.
  18. Eisenhower Memorandum, 22 March 1944, The Eisenhower Papers, 1784, 1786, n. 9.
  19. Eisenhower to Marshall, 12 April 1944, The Eisenhower Papers, 1817.
  20. Memorandum for Diary, 22 May 1944, The Eisenhower Papers, 1880-81.
  21. Eisenhower, Report of the Supreme Commander, 9-10.
  22. Eisenhower to Marshall, 12 April 1944, The Eisenhower Papers, 1817.
  23. Eisenhower, Report of the Supreme Commander, 9-10.
  24. Eisenhower, 10.
  25. Eisenhower, 9-10.
  26. Eisenhower to Marshall, 29 April 1944, The Eisenhower Papers, 1838; and Eisenhower to Churchill, 2 May 1944, The Eisenhower Papers, 1842-43, 1844, n. 1.
  27. Eisenhower to Churchill, 5 April 1944, The Eisenhower Papers, 1808.
  28. Eisenhower to Churchill, 2 May 1944, The Eisenhower Papers, 1842-43.
  29. Wesley F. Craven and James L. Cates, eds. "Europe: Argument to V-E. Day,", in The Army Air Forces in World War II (Washington, DC: Office of Air Force History, 1983), 74-75; and James. H. Doolittle, I Could Never Be So Lucky Again (New York: Bantam Books, 1991), 387-88.
  30. 22 March 1944, The Eisenhower Papers, 1784; Eisenhower to Tedder, 9 March 1944, The Eisenhower Papers, 1765-66.
  31. The Eisenhower Papers, 2033, n. 1.
  32. Eisenhower to Harris, 25 May 1944, The Eisenhower Papers, 1888.
  33. Eisenhower to Harris, 27 July 1944, The Eisenhower Papers, 2033; Operation Crossbow was the Allied attacks against German long-range weapons facilities.
  34. Craven, "Europe: Argument to V-E. Day," 76-77; Richard Davis, Carl A. Spaatz and the Air War in Europe (Washington, DC: Center for Air Force History, 1993), 345-46; and Arthur Tedder, Air Power in War (London: Hodder and Stoughton, 1947), 108. See also Richard Davis, Bombing the European Axis Powers: A Historical Digest of the Combined Bomber Offensive, 1939-1945 (Maxwell Air Force Base, AL: Air University Press, 2006).
  35. Eisenhower, Report of the Supreme Commander, 19-20.
  36. Eisenhower Memorandum, 3 June 1944, The Eisenhower Papers, 1905-6.
  37. Eisenhower, Report of the Supreme Commander, 16.
  38. isenhower Memorandum, 3 June 1944, The Eisenhower Papers, 1905; Eisenhower to the Combined Chiefs of Staff, 8 June 1944, The Eisenhower Papers, 1916.
  39. Martin Blumenson, Breakout and Pursuit, The United States Army in World War II: The European Theater of Operations (Washington, DC: US Army Center of Military History, 1984), 188-91.
  40. Blumenson, 221-22, 228-29.
  41. Blumenson, 233-36; Omar N. Bradley, A Soldier's Story, 349.
  42. Eisenhower, Report of the Supreme Commander, 35-37.
  43. Department of the Army, Field Manual (FM) 3-0, Operations (Washington, DC: 2017), 2-3, 2-45.