From: Cologne, Germany
Just a comment on this.
While Attu was hardly the most critical operation of the Pacific War, it did have more benefits than most give it credit for. Once Attu and Kiska were taken, Japan was forced to ship forces to cover all the Kuriles, provide garrisons (which peaked at nearly 100,000 men which were largely taken from China/Manchuria) and then supply those men. ...
Not sure where you got these numbers from, but they seem to be pretty exaggerated. The US Strategic Bombing Survey used and incorporated interrogations of Japanese officials, and the numbers stated in there are way lower:
ORIGINAL: United States Strategic Bombing Survey
NAVAL ANALYSIS DIVISION
Interrogations of Japanese Officials
"On 5 August 1943 the Japanese Northeast Area Fleet was organized, comprised of the Fifth Fleet and Twelfth Air Fleet. The Commander in Chief, Northeast Area Fleet was charged with the defense of the Kuriles Area and given tactical command of local base forces. An Imperial Headquarters Directive of 30 September 1943 stated, "object of Northeast Area Operations is to smash the oncoming enemy and to defend the Kuriles, Hokkaido, and other integral parts of the Empire. Simultaneously, and insofar as possible, enemy strength in the Aleutians is to be whittled down." Despite the last statement Japan was on the defensive in the Kuriles, and desperately concerned over an amphibious advance from that direction against the Empire.
An index to the importance which Japan attached to the defense of the Kuriles is indicated in the number of Army troops deployed there. From 14,200 men in late 1943 the garrisons were increased to a total of 41,000 men in mid 1944 and decreased to 27,000 men in 1945. These men were Japan's answer to the threat of United States invasion from the North via the Aleutians. The men were not in action, except in defense against harassing air raids, or against sporadic shore bombardment by light United States naval forces."
It provided easy pickings for US submarines (one in ten men assigned to the Kuriles did not make it there)...
The assessment, that these troops were missing (and badly needed) elsewhere and that convoys to the Kuriles were harrassed by submarines, is correct, though:
ORIGINAL: page 83
"However, they were required to maintain their defensive positions and hence were unavailable for combat assignment elsewhere. Moreover, their supply and movement afforded excellent shipping targets for aggressive United States submarines. This resulted in a heavy loss of ships to Japan as well as a loss at sea of about 10 percent of the total personnel deployed to the islands."
ORIGINAL: page 83
"In November 1943 an estimated 262 airplanes were in Hokkaido and the Kuriles, in about equal numbers for the Army and Navy. Air activity was confined to defensive fighter patrols and antisubmarine patrols except for a few Attu reconnaissance missions. Also one attack mission against Attu was conducted on 10 October 1943 by naval twin-engined land-based attack planes. Air strength in the Hokkaido-Kuriles Area in the summer of 1944 was approximately 500 planes. By the spring of 1945 practically all air strength had been withdrawn from the Kuriles except for about 18 Army fighter planes on Paramushiro and 12 Navy dive-bombers divided between Shimushu and Etorofu."
... and allowed raiding by US Navy/AAF pilots (as a part of Operation Wedlock) which forced Japan to keep a fair amount of aircraft in the region (roughly one tenth of their air power).
Actually, Allied air operations in the Kuriles theater remained to be on a really low level only, which resulted in the Japanese decision to withdraw all but 30 aircraft from the Kuriles, one and a half year later. These planes had been deployed there to bolster against an amphibious invasion on the Kuriles and to maintain a number of anti-submarine sorties:
ORIGINAL: page 87
"In later stages of the war aircraft maintained a steady though relatively small effort against the Kuriles in order to maintain, in conjunction with submarine patrols and surface ship sweeps, the attrition of shipping and the threat to Japan from the north."
When they held Attu and Kiska, those islands were held with far less men and aircraft than garrisoning the entire Kurile chain.
Well, the Japanese garrison on Attu/Kiska peaked at 8,500 men, but the Kuriles required a more dense defense network, because a successful invasion would have opened the door to Hokkaido. Still, initially the Attu/Kiska garrison amounted to ~59.8%, then 20.7% and 31.4% (in spring 1945, when troops from the Kuriles were needed elsewhere) of the troops stationed on the Kuriles.
If the Japs would have needed the islands for an invasion of Alaska, or for strikes even further south, they would have (and should have) placed more troops there. IMHO, it was rather a propaganda move, and - if at all - an operational diversionary move to conceal the deployment at Midway.
Whatsoever, Japan did not have the means to use these islands as staging area. The weather hampered supply efforts for the Japanese garrison on the Aleutians, and it also made the US opt out of considering the Northern route for an invasion of the Japanese mainland, though.
Later on, Japanese officers argued that the naval escort group (cruisers, carriers, etc.) provided for the Japanese invasion force could have made a difference, if it would have been committed to the operation at Midway instead.
Whatsoever, for the US, the Japanese troops on the Aleutians were rather like a disturbing "mosquito" humping around their neck, than anything else. Due to the weather conditions, with the dense summer fog and winter storms, the Aleutians became a vital playground for the employment of the first airborne radar devices (mounted on US boat seaplanes) in 1942, prior to the Japanese attacks, already, which helped to collect vital experiences regarding navigation and target detection for later use (radar-aided level-bombing in Germany, for example).
Clearing the Aleutians rather offered a strategical and political value to win the Russians over for entering the war against Japan:
ORIGINAL: page 84
"To be mentioned among the intangible results of the Aleutian Campaign was its effect upon the probable participation of Russia in the Pacific War. Russia was an ally of the United States in Europe and a potential ally in the Pacific. The probability of Russia's commencing hostilities against Japan depended in some degree upon the possibility of assistance reaching her by seaborne transport. An air route via Nome was in operation and over it was ferried a large number of lend-lease aircraft. The water route passed through the Aleutians and the Kuriles. In order to facilitate a future entry of Russia into the war against Japan it was necessary to secure this water route, which was done to the extent of expelling the Japanese from the Aleutians and weakening and containing their forces in the Kuriles."
< Message edited by GoodGuy -- 12/13/2011 2:02:55 PM >
General Anthony McAuliffe
December 22nd, 1944
"I've always felt that the AA (Alied Assault engine) had the potential to be [....] big."
8th of August, 2006