The air phase of Operation Cobra began at 10 am on the morning of the 25th. Some 1,503 of 1,581 B-17s and B-24s droppedtheir high explosive and fragmentation bombs on the Panzer Lehr Division. Joining the Eighth Air Force’s heavies were medium bombers and fighter-bombers. All together, the air effort dropped over 4,100 tons on German positions, killing over a thousand German soldiers, wiping out three battalion command posts, and destroying or severely damaging most of its armor and armored personnel carriers.
The effect of the bombing on the already understrength Panzer Lehr Division was significant. The German division commander, Lt. Gen. Fritz Bayerlein, described the scene outside of St. Lo in a postwar interrogation: “It was hell…. The planes kept coming overhead like a conveyer belt, and the bomb carpets came down…. My front lines looked like a landscape of the moon, and at least seventy percent of personnel were out of action—dead, wounded, crazed, or numb.” Bayerlein placed the actual losses of dead and wounded at approximately 50 percent by bombing, 30 percent by artillery, and 20 percent by other weapons.
Still, despite the devastating pattern bombing and the artillery barrage that followed, the Americans were unable to break through the German lines on the 25th. But the American commander opposite the most battered part of the Panzer Lehr Division’s lines, Maj. Gen. J. Lawton Collins, shrewdly realized that the German command and control structure had been badly disrupted by the air attack, and planned a full-scale attack the next morning. On the evening of the 25th, Collins brought his VII Corps armor, newly equipped with iron shears to bulldoze the hedgerows, to the front with orders to push through the remaining German defenders at dawn. In the morning the 2nd Armored Division, supported by tactical air and building on the accomplishments of the 30th Infantry Division, cut through the demoralized German defenders. Breakthrough had become breakout, and the race to Germany had begun.
Friendly Fire Killed 111 Americans and Wounded 490 More
The July 26 breakthrough at St. Lo owed its success to aggressive pattern bombing the previous day. Bradley’s use of heavy bombers in close air support of ground operations brought the weight of American airpower to bear against a vulnerable opponent at an opportune time. But the success of Operation Cobra was tainted by more friendly-fire incidents. Once again, American bombs accidentally hit units in the 30th and 9th Infantry Divisions.
In all, short bombs killed 111 Americans, including Lt. Gen. Leslie J. McNair who had come to Europe to assume command of the newly forming American Ninth Army, and wounded 490 more. Moreover, the close proximity of American troops to the intensive bombing caused 164 post-traumatic shock cases in the 30th Infantry Division, further reducing their combat efficiency.
High-level finger pointing took place as a result of the friendly-fire deaths. General Spaatz tried to place blame on the medium bombers of IX Bomber Command. The Eighth Air Force’s own investigation showed the 2nd Air Division was responsible. In his memoirs, General Bradley accused the airmen of “duplicity,” claiming they had told him the July 25 bombing would be parallel to the road. But Bradley and other ground commanders’ failure to pull their troops back from what was known as a very dangerous front raises their culpability. What is certain is that the blame for the short bombings does not rest entirely on any one service. Although there was no “duplicity” on the part of the Army Air Force (in fact, air commanders were reluctant to undertake the operation at all), airmen from Tedder and Leigh-Mallory to the bombardiers themselves deserve some of the blame.
Despite the demoralizing effect close air support had on friendly troops, American ground forces successfully pushed through the battered German defenders. The success of Cobra owed to many factors. Unlike Montgomery’s failure in Operation Epsom a month before, Bradley attacked with a much greater force against a critically weaker enemy. The German forces in Normandy had suffered seven weeks of attrition and were split between defending the strategic crossroads at St. Lo and the defense of Caen. Unable to reinforce either sector rapidly due to Allied air interdiction, short of ammunition and without Luftwaffe air support, the German line of defense was vulnerable to puncture.
Was the Operation Worth the Price?
Both Montgomery and Bradley recognized the utility of using heavy bombers in support of ground troops, but the failure of Allied heavy bombers to break the back of German resistance at Caen (causing considerable collateral damage to French civilian and friendly troops) did not deter Bradley from using them at St. Lo. Although friendly-fire casualties did occur in both operations, it was a relatively small price to pay considering the overall stakes. In July 1944, the breakout of Normandy had stalled, and without a determined Allied combined-arms offensive the very existence of a Second Front was endangered.
Operation Cobra vividly illustrated the firepower heavy bombers could bring in support of ground troops. Although an inexact science in the summer of 1944, the close air support operations in Normandy were the precursor to heavy bombers being used in later ground support missions in the European Theatre and later in Korea, Vietnam, and the recent Gulf War. Heavy bombers have proved a powerful addition to the arsenal of ground commanders, providing critical offensive mass at crucial moments.