 Following break @-@ out by the US 1st and 3rd Armies from the beachhead during the Battle of Normandy after Operation Cobra on 25 July 1944 , Adolf Hitler ordered an immediate counterattack against Allied forces in the form of Operation Lüttich . Lieutenant General Omar Bradley — the commanding general of the US 12th Army Group — was notified of the counterattack in advance through signals intercepted via Ultra radio intercepts and deciphering and thus prepared his troops and their commanders to defeat this counteroffensive and to encircle as much of the Wehrmacht force as possible . By the afternoon of 7 August , Operation Lüttich had been defeated by concerted , large @-@ scale fighter @-@ bomber air strikes against the German Panzers and trucks . In the process , forces of the German 7th Army became further enveloped by the Allied advance out of Normandy . 
