I think all WWII documents have been released haven't they? So it would've been luck...

Well Pearl Harbor turned out to be a blessing in disguise in a way, as I don't think the navy had fully accepted the effectiveness of the carrier. Pearl Harbor both proved the effectiveness of carrier launched aircraft, but also forced the navy to embrace them as their battleships had been devestated and the three carriers were the only ships left to take the core position in the fleet.