From the second report of 15 August 1939 from Coulondre to Bonnet, on the general situation in Germany:
Up to the present, if we except the assembling of troops in many places in Upper Silesia and in East Prussia, no important concentrations constituting an immediate threat to Poland have yet been observed. Technical experts, however, are of opinion that in the present state of German mobilization such concentrations could be effected in a few days.
(2) If, at the time of the Polish ultimatum of August 5, some surprise and some wavering was noticeable in the attitude of the Nazis in Danzig and in the Reich, Germany was, nevertheless, not slow in regaining her self possession.
After the Senate climbed down in the matter of the Polish Customs officers, the leaders of the Reich, tried, as we had for several days been given to understand from the German side they would, to take over the diplomatic representation of the interests of Danzig. This was the meaning of the verbal note handed by the German Government
to Warsaw on August 9. The Polish reply of the 11th in which the Warsaw Government declared that it would consider any fresh German intervention in the differences between Danzig and Poland as an act of aggression, cut short this attempt. This reply appears to have profoundly irritated the Nazi leaders and the Führer himself.
It is noteworthy that Coulondre admits that the Polish Government presented an ultimatum to Danzig on 5 August (actually 4 August). Under the terms of the Anglo-Polish Agreement on Mutual Military Assistance, that ultimatum could have triggered war between Germany and Britain, which may well have been the Polish intention.
Coulondre also reveals that Poland was not simply reacting defensively to real German aggression. As he confirms, when Germany tried to protect Danzig against Polish thuggery, in the form of the ultimatum of 4 August, the Polish Government reacted in an extremely aggressive manner, stating that it would regard German diplomatic intervention on the side of Danzig as an act of aggression against Poland.
It is clear that the Polish reply to Germany of 11 August was tantamount to a threat of war. Under the terms of the Anglo-Polish Agreement on Mutual Military Assistance of 6 April, if Poland declared a German diplomatic intervention on behalf of Danzig to be an act of aggression against Poland, and responded to it by mobilising its forces, Britain was obliged to go to war with Germany if called upon to do so by Poland.
That shows that Poland was fully prepared to plunge Britain and Germany into war over something as minor as a German diplomatic intervention on behalf of Danzig. It was by no means waiting to be an innocent victim of a German attack.
The only reason war between Germany and Polanmd, with Britain joining in against Germany, did not erupt over the Polish ultimatum to Danzig and the subsequent German diplomatic intervention is that Germany hastily backed down.
It also shows that the eventual German invasion on 1 September was a final, last-option response to Polish threats of war connived at by the British and French Governments (or at least by the "hawks" in those governments).
The principal dangers of war may, therefore, be reduced to these two:
(a) Illusion as to the attitude of France and Great Britain.
(b) The hope of being able to destroy the Polish Army before the Western Powers have been able to give effective assistance, and of having by this means created a "war map" which would set London and Paris thinking.
(a) There is no doubt that certain of the Nazi leaders and, in particular, Herr von Ribbentrop, still hope to give some sort of satisfaction to the Western Powers by restricting the German claims to Danzig, setting aside, provisionally, the question of the Corridor and other claims against Poland.
(b) The idea that the German Army could crush the Polish Army and take Warsaw in a few weeks, or even a few days, before France and England had time to intervene, or even to come to a decision, is fairly widespread among the public and in certain official circles. The Führer himself is said to consider the undertaking as not impossible. It is said that certain officers in his circle encourage him in that view.
What is most likely at the present time, is that Germany, while endeavouring to carry through the first solution (a) is continuing to push on her preparations with a view to being able if necessary to attempt the second solution (b).
Here Coulondre confirms that Germany's preferred option was to achieve an agreement with Britain and France on the future of Danzig, and that a military intervention against Poland was only its second option, to be resorted to only if the preferred option could not be achieved due to Polish obduracy backed up by Britain and France.
Coulondre also shows himself to be fully aware of the purpose of a German military intervention against Poland. Such an intervention would not have the purpose of destroying the Polish State and people, but rather of eliminating Polish military force as a factor in the encirclement of Germany, thereby "setting London and Paris thinking", to use Coulondre's words, ie to present the British and French Governments with a fait accompli that might in the most hopeful scenario deter them from proceeding to make war on Germany, but rather be prepared to negotiate a settlement.