Originally posted by Padma
If you dig through the actual historical record, like I have, you will find that other actions would be scheduled to take place on "A-Day", or "F-Day" or what have you. And these were before June, 1944. But you are correct, in that they decided to not use "D-Day" again after that.
(I love watching the History Channel myself, but they are not infallible.
)
I'd like to expand on this just a bit.
D-Day is a particular day on which some large military action is to take place. Using D-Day (as well as H-Hour and M-Minute) has several advantages:
* Everything connected with the operation is scheduled around D-Day. For instance, some necessary event can be scheduled for D-10 (D minus 10) or D+2.
* It's a code word that doesn't tell the enemy when something is taking place.
* If, for some reason, D-Day has to be changed, that doesn't change the major part of the schedule. Some event scheduled for D-1 will still take place on D-1 even if D-Day itself has changed.
Let's take the case of the WW2 Invasion of Normandy. Originally the invasion was to take place on June 5, 1944. Because of weather conditions, on D-1, D-Day had to be moved forward to June 6th. So everyone adjusted their schedules appropriately.
Later on, when D-Day became synomymous with the Normandy Invasion, other letters were used in place of "D." The invasion of Okinawa on April 1, 1945 took place on "X-Day" and the invasion of Iwo Jima on February 19, 1945 was on "L-Day."