October 24, 1941
: Admiral Yamamoto to (newly appointed) Navy Minister Shimada:
You have my sincere sympathy, as I can appreciate how complex must be the problems that are yours now in the wake of the most recent political change. I therefore consider myself extremely fortunate in being able to devote myself exclusively to the affairs of the fleet. On the basis of the various chart exercises and table maneuvers that were held since last year, I have come to the conclusion that however smoothly the southern operations may progress, we are bound to suffer considerable losses in heavy cruisers and lesser types by the time operations are completed under pressure; and in aircraft, we will probably expend two-thirds of its strength every day (and even of the remaining one-third, hardly any will be left in sound shape). The resulting situation, I am afraid, will find the Navy's strength stretched beyond the limit of its capacity. And in view of our very poor ability to replenish our air force, it will be virtually impossible for the Navy to meet the needs of the major sea battle that is likely to follow.
After much study, therefore, I have come to the opinion that the only way is to have a powerful air force strike deep at the enemy's heart at the very beginning of the war and thus deal a blow, material and moral, from which it will not be able to recover for some time. Judging from Admiral Kimmel's character and the recent trend of thought in the American Navy, it does not appear likely that the American Navy will necessarily confine itself to the strategy of a steady frontal offensive. And when I think what the strength of our homeland defense will be while the southern operations are in progress. I cannot but be truly apprehensive. Even if the southern operations develop to our advantage, I dread to think what our public (most of them being shallow-minded) will say of the Navy, I, in the course of these operations, enemy planes should suddenly raid Tokyo and Osaka and inflict even slight damage. We need only recall what happened at the time of the Russo-Japanese War.
I have recently heard that there are some elements in the General Staff who argue that since the air operation to be carried out immediately upon the outbreak of war was after all nothing more than a secondary operation in which the chance of success was about fifty-fifty, the use of the entire air force in such a venture was too risky for consideration. But even more risky and illogical, it seems to me, is the idea of going to war against America, Britain and China following four years of exhausting operations in China and with the possibility of fighting Russia also having to be kept in mind and having, moreover, to sustain ourselves unassisted for ten years or more in a protracted war over an area several times more vast than the European war theater. If, in the face of such odds, we decide to go to war—or rather, are forced to do so by the trend of events—I, as the authority responsible for the fleet, can see little hope of success in any ordinary strategy. Indeed, I would feel compelled to resort to the combined strategies of Okehazama, Hiyodorigoe, and Kawanakajima (Note: This is a reference to 3 ancient battles won by 3 different Japanese warlords using the tactic of a sneak attack).
These matters the senior staff officer of my fleet explained to the responsible authorities in Tokyo when he was there recently and obtained their approval, but there seem to be some who have misgivings as to my character and ability as supreme commander. The fact is that I do not consider myself qualified for the post of C-in-C of the Grand Fleet; and besides, there is no time to think of one's own interest in a time of such national emergency as the present...War with America and Britain should still be avoidable when the overall situation is taken into consideration, and every effort should of course be made to that end. But I wonder whether Japan, having been driven into the present situation, has the courage and the strength necessary to make such a change of attitude now. I fear with trepidation that the only thing that can save the situation now is the Imperial decision.