The Imperial Japanese Navy was best in the world in three things on Jan 1st 1942- attacking ships from airplanes, launching night torpedo attacks from cruisers and destroyers, and having the biggest, meanest battleship with by far the biggest guns and the most armor. Now, the Japanese navy picked very wisely- these were clearly the most important things in 1941, which was why they were so effective at fighting.
But, at best, they had parity with the USN in every other category. So, for instance, the USN was much better at receiving air attacks- they were about two years ahead on radar technology (which, given the pace of technological development in 1940 is the difference between your first experimental set and wide-scale operational deployment). They were much better at radios and communication (literally the Zero's radio was so useless that the standard way that surface ships communicated with friendly Zero's on CAP was to fire their main guns into the water, kicking up big spouts of water, summoning the Zeros to attack enemy planes near the ship). They were much much better at medium range AA fire (the USN developed the Mk. 37 Fire Control System, an analog gyrostabilized computer hooked up to the range finder which automatically slewed the gun turrets to the correct spot, adjusting for the wave motion of the ship. By 1944 it was so sophisticated that when an operator tracked the target in the range-finder it could even automatically set the timer on the shell for the correct time of flight for that distance). A lot of these advantages compound: for example, the RN never developed as sophisticated a fire control system as the Mk 37 because the USN had also developed more expensive and better (small-tube high pressure) boilers at about the same time. These more sophisticated boilers allowed USN destroyers to adopt unitized machinery- going boiler-turbine-boiler-turbine, so that one hit that took out two rooms wouldn't knock out power to the whole ship. The RN, with less sophisticated engineering plants (boiler-boiler-turbine-turbine), were much more focused on continuing to fight a ship after power was lost and so didn't try to develop that sort of analog computer system, and instead insisted that their turrets be workable against airplanes using purely manual controls. And this sort of superiority shows up again and again when you look at other areas: submarine warfare and anti-submarine warfare, UNREP, amphibious assault, etc. all of these other categories the USN was somewhere between slightly and extremely superior.
The Japanese, by carefully wielding those three areas of advantage, fought the larger USN to mutual exhaustion over the course of 1942, where both sides lost most of their carriers and other ships. But then by Operation Hailstone, the February 1944 raid on Truk, a totally different USN existed, which had been built during the course of 1942 and 1943, and that navy stomped through the remains of the IJN and has been the dominant naval force afloat for the past 80 years. ("There are three different navies that need to be understood to understand the Pacific War: the USN of Jan 1 1942, the IJN of Jan 1, 1942, and the USN of Jan 1 1944" as a historian once told me.)
And that other navy was built because, as smart and clever as the Japanese were, the US had twice the population and three times the per-capita income. In a war of national wealth like a naval-air war, that difference just couldn't be answered.
But, at best, they had parity with the USN in every other category. So, for instance, the USN was much better at receiving air attacks- they were about two years ahead on radar technology (which, given the pace of technological development in 1940 is the difference between your first experimental set and wide-scale operational deployment). They were much better at radios and communication (literally the Zero's radio was so useless that the standard way that surface ships communicated with friendly Zero's on CAP was to fire their main guns into the water, kicking up big spouts of water, summoning the Zeros to attack enemy planes near the ship). They were much much better at medium range AA fire (the USN developed the Mk. 37 Fire Control System, an analog gyrostabilized computer hooked up to the range finder which automatically slewed the gun turrets to the correct spot, adjusting for the wave motion of the ship. By 1944 it was so sophisticated that when an operator tracked the target in the range-finder it could even automatically set the timer on the shell for the correct time of flight for that distance). A lot of these advantages compound: for example, the RN never developed as sophisticated a fire control system as the Mk 37 because the USN had also developed more expensive and better (small-tube high pressure) boilers at about the same time. These more sophisticated boilers allowed USN destroyers to adopt unitized machinery- going boiler-turbine-boiler-turbine, so that one hit that took out two rooms wouldn't knock out power to the whole ship. The RN, with less sophisticated engineering plants (boiler-boiler-turbine-turbine), were much more focused on continuing to fight a ship after power was lost and so didn't try to develop that sort of analog computer system, and instead insisted that their turrets be workable against airplanes using purely manual controls. And this sort of superiority shows up again and again when you look at other areas: submarine warfare and anti-submarine warfare, UNREP, amphibious assault, etc. all of these other categories the USN was somewhere between slightly and extremely superior.
The Japanese, by carefully wielding those three areas of advantage, fought the larger USN to mutual exhaustion over the course of 1942, where both sides lost most of their carriers and other ships. But then by Operation Hailstone, the February 1944 raid on Truk, a totally different USN existed, which had been built during the course of 1942 and 1943, and that navy stomped through the remains of the IJN and has been the dominant naval force afloat for the past 80 years. ("There are three different navies that need to be understood to understand the Pacific War: the USN of Jan 1 1942, the IJN of Jan 1, 1942, and the USN of Jan 1 1944" as a historian once told me.)
And that other navy was built because, as smart and clever as the Japanese were, the US had twice the population and three times the per-capita income. In a war of national wealth like a naval-air war, that difference just couldn't be answered.