I'm a french history student and I had a hard time trying to find something about american memory of World War II. In France this is an important subject (around the collaboration and resistance), studied in highschool and widely developed as a concept in university.
In american popular culture, this is a very common subject as well, from Saving Private Ryan to games like Call of Duty. I've read a lot about the importance of the Constitution, the Founding Fathers even the Civil War but not much about World War II.
If you want to read something good about "collective memory" and Americans in WWII you have to change the terminology.
"Collective memory" just isn't a phrase many American academics who specialize in 20th century history use.
Some of the best big books about American experiences in WWII weren't written by academics.
If you are interested in the subject and haven't read it you should get a copy of Studs Terkel's book, "The Good War."
The buzz words American academics use are "oral history" or "historical trends" or "common man experience."
The other thing you need to realize is that the United States fought a war on two fronts. (It was actually a global war for the United States...) but that means that for millions of Americans their war was the Pacific, not the European theatre.
I agree, I think there's a terminology, and even methodological, difference at play. I've seen collective memory used as a frame of reference more in Latin American or early American history, but not much in 20th century studies. There's of course Tom Brokaw's book The Greatest Generation, which certainly would represent how some Americans remember the generation that went through WWII.
I also just did a quick search on my university's (I'm in the U.S.) library website, and there was a dissertation on ProQuest Central called Remembering World War II in the late 1990s: A case of prosthetic memory, by Bullinger, Jonathan. It looks interesting if you are able to see it.
I think most of the work on WWII might focus more on the experiences of soldiers, rather than on the memories of civilians. I'm sure there's also been significant study around collective memory of Americans who were put in Japanese internment camps during the war. Hope that helps a bit and best of luck!