The air wars in Europe and in the far east were way different.
No AA guns in the blue part of the map. No radar in the blue part (at least in 1941).
No telephone system to report enemy formations in some areas of the green and brown parts let alone the blue part.
Speeds and altitudes could be used in the Pacific that would have suicidal to try using in Europe.
For that favorite whipping boy for short range, the P-47, it's range depended on what you wanted it to do. It could fly over 800 miles on internal fuel but at a low speed (around 200mph) and a low altitude (5-10,000ft)
It took (clean) around 91 gallons of it's 305 gallons to warm up, take off and climb to 25,000ft. It only took 55 gallons to get to 10,000ft. At around 10,000ft that extra 36 gallons of fuel was worth around 125 miles of range at about 210mph. Combat radius has to plan for using fuel in combat and the P-47 could use up fuel over 4 times as fast at combat ratings as it did in slow cruise. Somewhat surprisingly the Zero, had it been used in Europe would have displayed a much shorter range. One book claims that while the early Zero could burn as little as 16.4 US gallons per hour at 180 kts ( altitude not given) just increasing to 190 kts increds fuel burn to 24.04 gallons an hour and 200kts took 26.15 gallons an hour. Max rated power took 91.14 gallons an hour.
Range with a 10 minute combat allowance was an astonishing 125NM. But 20 minutes of combat time chopped range to 900NM. Now try to figure what the range would be if they had to climb to even 20,000ft while the drop tank was near full and then cruise at 200kts or so.
Total fuel 228.5 US gallons (87.18 in the drop tank), 20 minutes of combat is worth about 30 gallons. Let's assume 30 gallons to get to 20,000ft (P-40E needed 40 gallons), that leaves about 160 gallons. At speeds of over 200 knts the extra low fuel consumption of the Sakae engine will tend to fade out.
Granted if you can't get into fight 200 miles away because you lack range you have problems, but if you can't climb to 25,000ft before the bombers have come and gone then you don't have much of an interceptor regardless of how rugged the plane is or how many bombs it can tote for ground attack.
British had somewhat solved the range problem on the Spitfire with the MK VIII (123 Imp gallons = 148 US gallons). All were sent overseas as the range problem was judged not that critical in Europe (other planes could do the long range escort).
I believe the US received about 600 Spitfires (reverse lend lease) many of which were used in North Africa/Med to provide top cover for those OH so versatile P-40s and P-39s.
