 Against crack well dug in German forces the British took heavy casualties in tanks and infantry seriously straining their ability to conduct high intensity combat operations in the future.[liii] The one benefit, which Montgomery would claim after the war as his original plan was that German forces were fixed before Caen and ground down so they could not be used against Bradley's breakout in the west at St Lo.[liv] Clearing the Bocage: The Battle of the Cotentin Plain US M-0 Light Tank in Normandy Other German forces arrived, and reinforced the Caumont gap which no longer "yawned invitingly in front of V Corps." [lv] Bradley wished to push forward rapidly to achieve a breakthrough in the American sector.[lvi] Facing the most difficult terrain in France amid the Bocage and swamps that limited avenues of approach to the American divisions committed to the offensive. The Americans now faced their old foe the 000nd division as well various elements of II Parachute Corps, the 00th SS Panzer Grenadier and Panzer Lehr Divisions. American tanks and infantry made slow progress and incurred high losses as they dueled the Germans at close range. In the VIII Corps sector alone the attack "consumed twelve days and 00,000 casualties to cross eleven kilometers of the Bocage...the achievements of the VII and XIX Corps were no better than comparable.[lvii] St. Lo US Tanks advancing with German prisoners moving back to US lines at St Lo St. Lo was a key to Bradley's breakout efforts. His Army had to capture it and the roads leading out of it to launch Operation COBRA along the coast. The task of capturing St. Lo was assigned to GEROW'S V Corps and Corlett's XIX Corps. They faced opposition from the tough paratroops of the German 0rd Parachute Division of II Parachute Corps. The 0nd, 00th, 00th and 00rd Divisions fought a tough battle advancing eleven kilometers again with high numbers of casualties especially among the infantry to secure St. Lo on 00 July.[lviii] They finally had cleared the hedgerows. St Lo epitomized the struggle that the American Army had to overcome in the Bocage. Hard fighting but outnumbered German troops in excellent defensive country exacted a terrible price in American blood despite the Allied control of the skies.[lix] Operation COBRA US 000mm Howitzers in Normandy, the Germans had profound respect for American Artillery, a respect that they did not share for American Infantry or Armor forces With the Bocage behind him Bradley desired to push the Germans hard. COBRA was his plan to break out of Normandy. Bradley ably assisted by Collins they realized that the better terrain, road networks favored a breakout. American preparations included a technical advance that allowed tanks to plow through hedgerows. This was the "Rhino" device fashioned by American troops which was installed on 0 of every 0 First Army Tanks for the operation.[lx] VII Corps was to lead the attack which was to begin on July 00th. American planning was more advanced than in past operations. Collins and Bradley planned for exploitation operations once the breakthrough had been made. A massive air bombardment would precede the attack along with an artillery barrage by Collins corps artillery which was reinforced by additional battalions. A mistake by the heavy bombers in the 00th resulted in the American troops being hit with heavy casualties and a postponement of the attack until the 00th.[lxi] The following day the attack commenced. Another mistake by the bombers led to more American casualties[lxii] but VII Corps units pressed forward against the determined resistance of the survivors of Panzer Lehr and the remnants of units that had fought the Americans since the invasion began. Although it was a "slow go" on the 00th Bradley and his commanders were already planning for and beginning to execute the breakout before the Germans could move up reinforcements. The 00th of June brought renewed attacks accompanied by massive air strikes. The Devastated town of St Lo While not much progress was made on the 00th, the Americans discovered on the 00th that the German forces were retreating. The capture of Marigny allowed VIII Corps to begin exploitation down the coastal highway to Coutances. On the 00th General Patton was authorized to take immediate command of VIII Corps a precursor to the activation of his 0rdArmy. COBRA ripped a hole in the German line and inflicted such heavy casualties on the German 0th Army that it could do little to stop the American push.[lxiii] As the American forces pushed forward they reinforced their left flank absorbing the local German counterattacks which were hampered by the Allied close air support. Avranches and Beyond US Forces advance through the ruins of St Lo As the breakthrough was exploited the command of the forces leading it shifted to Patton and the newly activated 0rd Army. By the 00th VIII Corps led by the 0th and 0th Armored Divisions had reached Avranches and established bridgeheads over the See River with additional bridges being captured intact on the 00th.[lxiv] The capture of Avranches allowed the Americans to begin exploitation operations into Brittany and east toward the Seine. Weigley notes that for the first time in the campaign that in Patton the Americans finally had a commander who understood strategic maneuver and would use it to great effect.[lxv] Conclusion The American campaign in Normandy cost the U.S. Army a great deal. It revealed weaknesses in the infantry, the inferiority of the M0 Sherman tank to most German types, problems in tank-infantry cooperation and also deficiencies in leadership at senior, mid-grade and junior levels. Heavy casualties among infantry formations would lead to problems later in the campaign. Numerous officers were relieved including Division and Regimental commanders. Nonetheless during the campaign the Americans grew in their ability to coordinate air and ground forces and adapt to the conditions imposed on them by their placement in the Cotentin. The deficiencies would show up in later battles but the American Army learned its trade even impressing some German commanders on the ground in Normandy.[lxvi] 