318 Mr R. G. Casey, Minister to the United States, to Department of External Affairs
Cablegram 159 WASHINGTON, 24 February 1941, 12.15 a.m.
For Chief of Naval Staff  from Naval Attache. 
Fifth Progress Report.
(1) Following is summary vide last paragraph of telegram No. 151.
 The views expressed have received the approval of the United States Chiefs of Staff but have not, as far as is known, been discussed with the State Department.
(2) General. The United States representatives find themselves unable to subscribe to the view expressed in paragraph 6 of my telegram No. 151. They consider that the retention of Singapore is 'very desirable' and that its loss would be 'unfortunate' but they hold that its loss 'would not have a decisive effect on the issue of the war'.
(3) In support of this view, they argue:
(a) Invasion of Australia and New Zealand or India beyond the present resources of Japan.
(b) Distances make serious Japanese attack on sea operations in the Indian Ocean unlikely, and the United States could ensure the security of communications from Australia and New Zealand to the Western hemisphere and thence to the United Kingdom.
(c) Proportion of the material support to the war effort which is now provided by Australia and New Zealand might be replaced by further supplies from the Western hemisphere.
(d) The loss of raw materials now drawn from Malaya and Netherlands East Indies would not be fatal. Replacements could in time be found from elsewhere.
Despatch of United States capital force to Singapore (4) United States representatives finally rule out the possibility of the despatch of United States capital ship force to Singapore, arguing:
(a) Such a deployment would be inconsistent with the fundamental principle of the United States policy that the Western hemisphere must remain secure. In the event of British defeat the United States must have immediately available for use in the Atlantic and Pacific naval forces capable of withstanding attack from overseas.
(b) Associated Far Eastern bases are incapable of protecting and supporting a battle fleet and in view of the needs of the British Isles it would be impossible to collect enough shipping to maintain a large fleet in that region.
(c) Associated naval strength in the Atlantic requires the maximum possible augmentation in order to bring about the defeat of Germany.
(5) They suggest that if, in spite of these arguments, we still maintained that it is essential to send reinforcements to the Far East, necessary naval forces should be British and should be released from the Atlantic or Mediterranean in the light of substantial United States naval reinforcement proposed for these theatres. This suggestion, which at first sight would appear quite illogical in view of paragraph (4) (c) above, is put forward reluctantly and is based on the contention that it is preferable for armed forces of each nation to operate in areas in which its own interests are primarily involved.
Reinforcement of Asiatic Fleet (6) United States representatives refuse to contemplate any reinforcement of their Asiatic Fleet either now or on the outbreak of war. In support of this they argue:
(a) It would be strategically unsound to detach any forces from the Pacific Fleet which would then have difficulty in taking offensive action, to divert the Japanese naval strength away from Malaya. Any reinforcement of the Asiatic Fleet could therefore only be at the expense of the United States naval effort in the Atlantic, which effort they are not prepared to reduce.
(b) It would be strategically unsound to locate any additional surface forces in the Philippines during peace time. Far from being a deterrent such forces would invite attack because they would be far from support by the Pacific Fleet. It would be politically impossible to locate any such forces at British, Dutch places in advance of war.
(c) Any additional submarines would have to come from the Pacific fleet, whose submarine strength is already ample for 'effective diverting action' or alternatively from the Atlantic contribution.
(d) Despatch of additional aircraft might act as a deterrent, but could not long delay loss of Philippines. Any such contribution however would be at the expense of the Atlantic theatre.
(7) United States representatives consider that it would be a serious mistake for the United Kingdom in making their strategical dispositions to withstand a Japanese attack against Singapore to count on prompt military support by United States. In support of this they argue:
(a) It is most unlikely that United States would declare war against Japan solely because that country had occupied Indo-China or Thailand.
(b) There is serious doubt that United States would immediately declare war against Japan were she to move against Malaya, British Borneo or the Netherlands East Indies, unless the United States were previously at war with Germany and Italy. Congress before deciding whether or not to declare war against Japan for infringing Malaya, almost certainly would require a considerable period for debate.
(8) Discussions on this subject will be resumed Tuesday February 25th.
(9) It is essential at this stage that no effort be made to bring any political pressure to bear in respect of the subject matter of above message. Grateful therefore if no reference be made to contents of this telegram. Minister  fully concurs.