Really? The Warhawks and the Airacobras pretty much held the fort in the Pacific theater until the newer Lightnings and Mustangs and Thunderbolts got there. Yeah, the high-alt performance of the P-39 and P-40 was lamentable, the British found that out soon enough when they tried it against the Luftwaffe. But in the Pacific theater, most of the air battles were below 5000 feet. When flown to its strengths- high diving speed, high firepower, high level speed- the P-40 was a handful for the Zeros and Oscars. One must remember that the Japanese pilots at the beginning of the war were superbly trained as well. Completely different design philosophies behind the two planes (P40 and the A6M Zero).
Don't forget that the Flying Tigers flew P-40s. The P40s did pretty well in the desert with the RAF and the RAAF, and in the Russian theater.
If anyone's interested in the Pacific theater air war, I suggest you read these two books.
#1. Zero: Masatake Okumiya (sp?), Jiro Horikoshi (sp?), Martin Caidin
#2. Samurai: Saburo Sakai, MArtin Caidin.
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