Originally Posted by GrauGeist: The element of surprise is absolutely key in this situation, however, as historically happened, the Japanese were able to close their taskforce within striking range unchallenged and delivered a series of attacks while everyone on Oahu were enjoying the start of a relaxed Sunday.
The strike force was over 280 miles away when they launched to avoid detection. Sending in a large landing fleet would have increased significantly the risk of alerting the Americans. As it were, the fleet would have been spotted by 0600 off the coast even if it was caused by gun fire. This would have given the AAF over one and a half hours to alert their crews and prepare their aircraft.
And yet the Island's defenses didn't spring into action as the Japanese aircraft passed overland but virtually as the bombs were falling...
Originally Posted by GrauGeist: With this in mind, assault forces closing under the cover of the night/dawn to coincide their approach during the air attacks (on or before 7:00 a.m. OR as originally occurred) would certainly offer positive results.
The air attack commenced at approximately 0750.
Yep, you found one of my many typos...
Originally Posted by GrauGeist: The bulk of U.S. forces were in and around the vicinity of Pearl with a few auxillary fields and air stations about the island. These smaller fields did not have a large amount of first line aircraft that would have been able to muster more than token resistance.
Wheeler airfield and Schofield barracks are in the middle of the island 10-15 miles away from the sea shore.
And the initial airstrikes pass right over Schofield Barracks...along the highway the that attack flights followed, leading them right to Pearl. And Schofeild Barracks took a beating in the air attack as it was. As did Bellows, Wheeler, Hickam and Kaneohe fields. The Japanese did miss the auxillery fields at Kahuku, Haleiwa and Mokuleia. Haleiwa was where several P-40s were able to get up and engage the Japanese, downing several.
Two mountain ranges with limited easily defended passes, like Pali Pass, running from north to south along the east and west coast of Oahu would make invasions here risky due to limited maneuver room and overlooking high ground. This would be similar to the Japanese attempt to take Port Moresby. The only viable invasion route would be on the north shore and down through the middle. But, this route takes the Japanese directly into the strength of the defending forces. See pix (from wikipedia) of east coast, west coast, and topological.
General Short, while being out to lunch as far as airborne attack, was apparently very diligent in preparing for an invasion and rehearsed defensive tactics often.
I think you are underestimating the quality of forces on Oahu verses PI. There were about 17000 US forces in the PI, some were guard units(Wikipedia) vs about 43,000 Army troops in Hawaii, and these were apparently well trained on counter-invasion activities by Gen. Short, who had no concept on defense from air attack. If I remember correctly, most of the new pilots at PI were right out of flight training. I suspect the pilots at Oahu were much better and indeed the few that got into the air performed bravely and effectively. Only about 10 AAF planes got aloft and they shot down as many as 6 Japanese. The Japanese two raids only consisted of 43 and 35 A6M respectively. I suspect that if these raids had been met by 40-60 P-40s with this quality of pilots the air battle would have changed considerably.
The Japanese had over 400 aircraft at their disposal (from 6 CVs) although (obviously) not all were committed. And as we have seen, the air raids did indeed catch the U.S. forces off guard and the U.S. fighters that did get up, made a phenomenal effort, but came up short.
We also might be underestimating the quality of the IJA troops. Since Japan has been already at war and an invasion of this caliber would not be seeing green troops committed, but rather combat seasoned troops rotated out of other areas for this operation. That being considered, how well would the U.S. troops perform, the vast majority having never been in combat? Also, Japanese have severely weakened the Naval and Army air assets, which establishes air superiority or soon will, with successive air attacks and CAP sweeps. Like I mentioned before in this possible situation, the assets intended for the invasion of Alaska would be diverted to the invasion of Hawaii and augmented as much as possible to ensure success.
If the air attack commenced prior to the landings, the U.S. defenses would be on high alert (as they were) but how well would they be ready to deal with the landings? Add to this, the fact that the bulk of the U.S. 7th fleet is burning and sinking in the harbor as the IJN battleships and cruisers are closing in to assist the landing forces?
Some good maps showing the military bases and the highway system along with the 2 Japanese attack waves:
So the bottom line here, is that if everybody was enjoying a lazy Sunday morning and looking up and waving at the passing Japanese aircraft as they were inbound, why should they think anything different about ships on the horizon? As many were used to the comings and going of U.S. naval assets and aircraft in the area, why would they suddenly be alarmed at the sight of distant ships and not aircraft?
Even after the USS Ward caught the IJN mini sub and sank it at the harbor entrance, no one reacted with any alarm.
So this scenario is calling for the same relaxed attitude on that morning, the same failure in communications, the same failure in radar recognition (and again, communications), the same failure in aircraft dispersal, the same failure with locked ammunition access, the same failure in active command, the same capital ships with cold boilers and on and on....
so many mistakes were made that morning. These is the conditions that I am proposing that exist when the Japanese come not only with aircraft, but an invasion.