288 Mr A. S. Watt, First Secretary of the Legation in Washington, to Mr R. G. Casey, Minister to the United States
Memorandum 12 February 1941,
UNITED STATES POLICY IN THE PACIFIC
1. During the past few weeks there has been increasing evidence that Japan intends to make a major move south in the near future.
No single piece of this evidence is strong enough to justify the conclusion that she has finally and irrevocably made up her mind to attack the Netherlands Indies or Malaya or both, but the cumulative effect of small bits of evidence suggests that she will 'spring' as soon as the appropriate moment arrives. This moment may be a specific date in the near future or an indefinite date which will be made definite only when Japan feels that German action in Europe or the Mediterranean or both has brought the most favourable moment in which to carry out her schemes.
2. Although some think that Japan will move on a fixed date (for instance, February 18th has been suggested), others, including Sir John Latham  and Dr. Hornbeck , are inclined to doubt whether she has any fixed date in mind. This latter view appears to be supported by the fact that, so far as one can gather, Japan is still not quite ready to move. She is still acting as mediator between Indo-China and Thailand and these negotiations are not yet complete. Assuming that they end shortly and that Japan, as the price of her mediation, secures further bases in Indo-China and other bases in Thailand, possibly as far south as Sangkla , these new bases cannot be made effective overnight. There may, therefore, be a period of some two to six weeks during which diplomatic and military steps can be taken to deter Japan from her southward move and in which to increase the defences of the threatened areas.
3. One can assume with confidence that Japan will not take any step (such as an attack on the Philippines) which will inevitably bring her into a war with the United States. It is very possible, however, that she may attempt to capture Singapore, either by land or sea or both. If she succeeded in taking Singapore, it is highly unlikely that the Dutch East Indies would resist Japanese pressure.
4. The outstanding question at the moment is to determine what action, if any, the United States is prepared to take to prevent Japan capturing Singapore.
5. It is now clear from President Roosevelt's own statement  that if Japan attacks the Philippines America will fight. It is not clear what America will do in any other set of circumstances and the next week or two may be the last chance of converting her to a British Empire point of view before Japan moves.
6. On its face, it seems clear that it is vital to the United States to prevent Singapore falling into Japanese hands. The naval defences of the Philippines are not such at present as to make it possible to base there an American battle fleet. Apart from Hawaii, Singapore is the only other place where a battle fleet can at present be based in the Pacific, except perhaps Sydney. So long as it remains in British hands, action by Japan towards Australia and the Netherlands Indies can only be precarious. The United States can continue to draw from the Netherlands Indies supplies of rubber and tin (she has only 3 1/2 months supply of each) which she needs. If, on the other hand, Singapore passes into Japanese hands, then the Philippines themselves will not be safe, Japan will control the Netherlands Indies and thus put herself in a position to cut off essential American supplies and will also vastly increase her own vital resources; and it will be extremely difficult to throw Japan out of Singapore even after the conclusion of a successful war against Germany and Italy.
7. These facts seem so obvious that it is hard to believe they are not accepted by American naval opinion. Yet in the talks which have recently been proceeding it would appear that the Americans are not prepared to admit the vital strategic importance of Singapore or to admit that, while Singapore and the Philippines are safe in British and American hands, it is unnecessary to the defence of the United States to station the whole Pacific fleet at Hawaii.
8. The attitude of the American Naval Committee can be interpreted along two lines:
(a) That their strategy is essentially unsound, or (b) That, under political instructions, they are deliberately arguing a case whose unsoundness they realise.
While the British delegation is, I think, inclined to adopt the first interpretation, it seems to me a rather dangerously easy one to adopt. I feel that at least full consideration should be given to the other possibility, which might be explained as follows:
9. The American Administration has for long tried to induce the British to send additional warships to Singapore, which suggests, incidentally, that they are very anxious that Singapore shall not fall. On the other hand, they have resisted all pressure from Great Britain to send American warships to Singapore. This may be because they feel that such action would be taken by Japan as a casus belli and 'provoke' a Japanese-American war in the Pacific.
Or, the Administration may feel that American public opinion would not sanction such a move, partly because it would seem provocative and partly because Americans feel more comfortable with the Pacific fleet based on Hawaii, even though naval strategists might agree that it could more effectively be based elsewhere. It is just conceivable, therefore, that the attitude adopted by the American naval representatives is to be regarded as a gigantic bluff, designed to compel Great Britain to reinforce the fleet at Singapore, even though she must seriously weaken her situation in the Mediterranean by so doing. It may be that, when pressed, America would be herself prepared to transfer to the Atlantic (and, in the event of war between America and Germany-to the Mediterranean as well) sufficient warships to replace those Great Britain had been compelled to send to Singapore. The Administration may feel that war with Germany in the next few months is highly probable and that American public opinion would support the use of American warships in the Atlantic and the Mediterranean. In these circumstances, they may prefer this roundabout and technically inefficient way of reinforcing Singapore to the more obvious solution of sending American warships to Singapore from Hawaii.
10. Two major points now require consideration. The first is what action the United States can be induced to take with a view to deterring Japan from starting a war with the British Empire. The second is, assuming such a war begins, what assistance is the United States prepared to give.
11. The need for 'deterrent' action has already been made abundantly dear to the Administration, not only by Lord Halifax  but also by the American Ambassador in Japan.  It seems probable that Mr. Hopkins on his return to America  would be prepared to add his voice in support of the argument. Both the President and the Secretary of State  are considering various things which the United States can do. Some of these, for instance a 'strong' reception to the new Japanese Ambassador , are likely to happen. It is doubtful, however, whether the Administration is prepared to take the only action which would have a reasonable chance of success, namely:
(a) A flat declaration that a Japanese attack on Malaya or the Netherlands Indies will mean a war with the United States or (b) The transfer of American warships to Singapore or (c) Substantial reinforcement of American warships in the Philippines or in the Asiatic squadron.
Strong pressure upon the Administration to do one or more of these three things is desirable. If this pressure fails the only thing left seems to be to make it as clear as possible that Great Britain does not intend to let Singapore fall, that, if necessary, she will send sufficent ships from the Mediterranean fleet to Singapore, that this will mean a major deterioration in favour of the Axis powers in the Mediterranean, thus inevitably lengthening the war and making the danger to America itself across the Atlantic more real. In these circumstances it may be possible to induce the United States to agree to make available in the Atlantic and, if necessary, in the Mediterranean itself, sufficient ships to replace the British ships sent to Singapore.
12. If war does break out between Japan and Great Britain and on the assumption that American warships are not already in Singapore, the greatest pressure should be brought to bear on the Administration to convince them that Singapore cannot be allowed to fall into Japanese hands, and to induce them to take whatever action is possible to preserve in British hands those islands and naval bases to the East and North of Australia which would assist any American fleet trying to get to Singapore. If they will not take this action, the only other thing left is to try to convince the Administration that, as British ships must leave the Mediterranean for Singapore, American ships must be made available in the Atlantic and perhaps even in the Mediterranean to replace them.
A. S. W[ATT]