. . . and learning things like the poor quality of our 5" anti-aircraft ammunition.
Boy, that period was a litany of how unprepared we were. When the USS Langley was under horizontal bomber attack in early '42 their WWI 3" couldn't reach higher that 15,000 feet. The Japs quickly recognized that, came in at about 17,000 and used the attacks as a training session for the green pilots and bombardiers.
On Bataan, we had WWI Stokes mortars that had an 80% misfire rate. The few times we retook a position, the contemptuous Japs had left flowers stuck in the tubes. I also understand that the Filipinos were issued M1917 Enfields that were missing cartridge case extractors, so they had to carry a wooden ramrod to knock out the cases.