Operation Cobra was the codename for the World War II operation planned by United States Army general Omar Bradley to break out from the Normandy area after the previous month's D-Day landings.

On July 10, 1944, Bradley revealed these plans to British generals Bernard Montgomery and Miles Dempsey. Montgomery and Dempsey agreed to supply the supporting attacks for the American advance in this operation up to Caen. As they proceeded, however, Montgomery and Dempsey planned an alternate breakout of Allied forces before the Americans, Operation Goodwood.

Goodwood's failure—over seventy Shermans were destroyed in the operation—on July 18 nonetheless diverted the majority of German armor east of the Americans' position. On July 24, B-17s from the Eighth Air Force attempted to soften up German defenses. Bradley called the attack off at the last minute, but 300 B-17s did not receive the message and, hindered by poor visibility, dropped 700 tons of bombs on the first day and 3300 tons of high explosive on the next morning, some on American as well as German positions.

The stunned American troops on the front line went ahead with the attack anyhow, ripping their way through the bocage which had hindered their Sherman tanks before. Late on July 28, the advance guard of the US VIII Corps rolled into Coutances on the western end of the Cotentin peninsula, penetrating the German line for General Patton's US Third Army to advance through into northwestern France.