This doesn’t really have anything to do with Pearl Harbor, though. The United States had the time certainly understood, and had built and deployed, the implements of air power. It was, after all, the U.S. Navy’s aircraft carriers that stopped the Japanese offensive in the Coral Sea and won the day at Midway. Those were all built before Pearl Harbor.
Yes, but the fleet wasn’t built around them like the Japanese fleet was. We were still stuck in the “battleship navy” way of thinking. It was only Pearl Harbor, which left us with nothing but carriers and subs to sink that mind-set.
Indeed, it’s probably correct to say it’s the main thing.
In no way is that different from the way the Imperial Japanese Navy was built; THEY had a battleship-heavy navy as well.
At the time of the Pearl Harbor attack the IJN deployed 10 battleships (Kongo, Hyuga, Hiei, Kirishima, Haruna, Mutsu, Fuso, Yamashiro, Nagato, and Ise) 18 heavy cruisers and 20 cruisers, plus more than a hundred destroyers and 68 fleet subs, along with six full sized carriers and two light carriers. It’s just not the case that the Japanese were somehow more forward thinking in that particular regard; the U.S. had put plenty of effort into naval air power.
Pearl Harbor worked not because of a particular technological failing on the part of the USA, but because of a failure in strategic and tactical intelligence; they did not expect the attack to land on Pearl Harbor, and blew several chances to detect the approaching attack force.
And, according to the movie (borne out by my subsequent cursory research), because of massive failures of communication. Good thing we’d learned a lesson from that, 60 years later.
It was complacency and an inability to guess correctly the intentions of potential or actual enemies.
It matter little how much information you have if you don’t tie it correctly to the intentions of the other guy.
Complacency is like gravity, it’s always there. Something happens and everybody springs to attention and is on the alert. You can’t be on high alert forever so as time passes and nothing happens the alert level gradually reduces. Finally the alert becomes just a routine, pro forma exercise carried out for the purpose of filling in the blanks on a report to headquarters. “Have heightened security measures been instituted?” “Yes.”