What If D-Day Had Been a Disaster?

According to Almost History by Roger Bruns (page 2), Eisenhower prepared a handwritten note, which he put in his wallet, to be used in case the landing of Allied forces on the beaches of Normandy was a failure. It read:

"Our landings in the Cherbourg-Havre have failed to gain a satisfactory foothold and I have withdrawn the troops. My decision to attack at this time and place was based upon the best information available. The troops, the air and the Navy did all that Bravery and devotion to duty could do. If any blame or fault attaches to the attempt it is mine alone."