319 Mr R. G. Casey, Minister to the United States, to Mr R. G. Menzies, Prime Minister
Cablegram 106 WASHINGTON, 30 May 1940
IMMEDIATE FOR PRIME MINISTER PERSONAL SECRET
I had a most important talk with Sumner Welles  at noon today.
I can talk freely and easily with him and he is friendly and receptive.
I painted the following picture to him:
I said that it was Bruce's strongly-held opinion that the French would crack sooner or later, probably sooner.  It was problematical whether Germany would exert her great effort on France or Britain first, but that he thought they would endeavour to clean up France first probably with the help of Italy, and that when that was successfully accomplished they would be free and in good position to concentrate all efforts by sea and air on Britain.
Welles asked if it was our belief that Germany could succeed in destroying the British resistance by land and air. I said that it was our strong belief that if Germany were prepared to lose sufficient men she could overwhelm Britain. I reminded him of the enormous superiority of Germany over Britain in land troops and their equipment.
I reminded him that with France defeated German air strength was quite certainly considerably more than double and possibly treble that of Britain herself, and that Britain had suffered very heavy losses in the only type of naval vessel that was any use in combating attempts at German landings on British soil, and that was destroyers.
I asked him to visualise the effect of large numbers of parachute troops dropped on Britain at and before dawn, and also to visualise the degree of dive bombing and machine gunning that could and would undoubtedly be brought to bear in a supreme effort to create confusion and chaos.
He asked me several times if I believed it was possible for a successful landing of any considerable number of German troops to be carried out in Britain. I said that such landing in force was perfectly possible although the German losses would undoubtedly be very great.
He asked if we thought that Germany could land tanks in Britain. I said that once an effective land area of Britain had been made good by Germany it was quite possible.
He asked me what function the British Fleet would play in such circumstances. I said that I could not conceive any useful function other than that of attempting to destroy any major units of the German Fleet that might venture out. Germany would use submarines fast motor torpedo boats and destroyers against which only destroyers were deterrents and Britain was now very short of destroyers.
I said that it was undoubtedly the conviction of the British Government today that there was no hope of the United States entering the war on our side. He questioned this but I persisted in this point of view and said that I knew that it was impossible for the Government and people in Britain to believe otherwise.
He knew of my recent discussion with the President  and he asked what I thought the British Fleet would do if Britain were overwhelmed. I said that I believed that the British Fleet would not give itself up under any circumstances but that they would probably immolate themselves by an attack on German naval ports.
He said that this would be an extremely unwise and illogical thing to do because whilst the British Fleet remained in existence it was possible to retrieve the situation at some later date.
In reply to this I said that if they thought in Britain that there was some eventual chance of the United States entering the war on our side that they might go to some lengths to maintain the British Fleet in existence, but that if they were convinced that America would never enter the war I believed that logic would be supplanted by spirit and passion as I had described. I said that I believed that there was only one person in the world who could save the British, French and Dutch Empires, and that was the President.
Welles said that the logic of the situation was that the British Fleet ceasing to exist was against the vital interests of the British Dominions. I said that I entirely agreed but that in the terrible conditions that Germany would probably be able and determined to bring about in Britain logic was most unlikely to be uppermost in British minds. Under certain violent circumstances even the sturdiest people ceased to take a long range view and would think only of themselves and their honour. There was only one thing that was likely to influence their minds and that was whether at some point in time not too remote America would be in the war with them. If they knew this it would quite certainly influence them as to what the British Fleet would be ordered or allowed to do with itself.
Welles said that I had painted a much graver picture than he had conceived. I said that I was convinced from the sources of information that were available to me that it was far from being an exaggerated picture.
I said finally that I believed that the time when material assistance was of real value was passing and that political assistance in the shape of a declaration by the United States would soon be the only thing that could save the world.
At the end Welles said that he accepted what I had said to him as genuine and that he would speak to the President at once. He said that in the present state and trend of public opinion here a week or ten days could produce great changes.
You will realise from this telegram and from telegram No. 100  that the eventual fate of the British Fleet is of great interest to this country. They have woken up to the fact lately that the British Fleet has been protecting the United States and the Monroe doctrine for a hundred years.