Here's the trend over time for the percent of books in Google's digital library (American English) that have the phrase "Pearl Harbor" or "September 11" --
Within 7 years of Pearl Harbor, the attention that writers paid it had settled down to its long-term level, far lower than in the immediate aftermath of the attack. I assume the blip in 1991 is just a 50th anniversary thing.
With 9/11, the print culture can't seem to shut up about it, even if most people aren't as afraid of terrorism as they were. Part of that is due to the attack hitting the home town of American publishing. Not to mention that the attackers were Muslims, who are more frightening than the Japanese to the disproportionately Jewish make-up of the media power centers.
Still I think the other, larger part is that Americans in general are just a lot more weepy than they were 70 years ago. And we're far more into the victimhood paraphilia, as shown by the sharp rise over the past decade or two in "torture porn" movies, not just horror but blockbuster dramas like Saving Private Ryan. We're supposed to identify with the suffering of totally helpless victims, rather than the courageous stand taken by the would-be targets of the enemy.