Well, since I'm mentioned, I guess I should at least give it a shot huh? This is a quite detailed analysis of the FOLLY of Japan trying to force an invasion of Hawaii. There is almost NOTHING to gain from such a venture except the MINOR inconvenience of denying an enemy a base of operations.

Goto:

The Hawaiian Invasion, and other Nonsense


And scroll down to "other really crazy", and read up on the limits of Japanese transports...

You might also "enjoy" reading If Mahan Ran The Great Pacific War; by John A. Adams. He discusses at length the problems of such an invasion for Japan, logistically, tactically, and strategically. There were appoximately 60,000 armed military personnel in Hawaii plus a civilian militia who would be drafted/volunteer to help fight. Let's not forget that the highly decorated 442nd was made up mainly of Hawaiian men who were removed from the island after the Pearl Harbor attack and sent to the mainland for "further" training. They fought the Germans, and had felt betrayed by Japan and wished they could have fought in Hawaii.

Using the accepted ratio of invader to defender, a three to one advantage is the normal so the Japanese would need about 200,000 men, and supplies, to invade with any hope of success, not 50,000.

The War Department (by September 1941), prescribed an impressive allotment of antiaircraft and artillery weapons for Hawaii: 84 mobile and 26 fixed 3-inch guns for level and high altitude firing, and provision for replacing some of them as soon as possible with even more modern weapons; 144 of the newer 37-mm. automatic weapons; and 516 of the .50 caliber antiaircraft machine guns for action against low-flying aircraft. This ignores the shore batteries which existed, mostly six and eight inch cannon.

By the time of Pearl, the Hawaiian department had four antiaircraft regiments, and it was scheduled to receive a fifth before the end of the year, it and its personnel were still on the mainland on Dec. 7th but were on the island by the end of December.

In the year preceding the Pearl Harbor attack, the Army's officer and enlisted strength in the Hawaiian Department (ignoring Navy and USMC numbers) grew from 28,798 to 43,177, and Hawaii remained the largest of the overseas garrisons. Only the Panama Zone held more American troops when the Japanese attack on Hawaii came, there were nearly 58,000 Army troops on guard in the Canal Zone, but they could have been transferred to Hawaii if needed to counter an invasion.

Now, since Hawaii gained the Japanese nothing but another far flung outpost, what would be the advantage? Let’s not ignore the real Japanese experience at Guadalcanal. This shows the limits of their logistics tail when it came to supporting troops any great distance away from their main bases. The Japanese called Guadalcanal "starvation island", and the commander there pleaded with his superiors not to send more troops, as he couldn't feed the ones who were already there!

The Japanese navy literally had no fleet oilers, troop transport ships, nor cargo transports for supplies, and was reduced to using destroyers as supply ships and troop transports, a terribly inefficient way to transport men and supplies. The guantlet to run to Hawaii would be no less dangerous.

__________________
Happy Trails,
Clint.