Urged on by Scheer, Holtzendorff submitted a new memorandum to Hindenburg on 22 December 1916, calling for the implementation of unrestricted submarine warfare no later than 1 February 1917. In his accompanying summary Holtzendorff argued, ‘A decision must be reached in the war before the autumn of 1917, if it is not to end in the exhaustion of all parties, and consequently disastrously for us. Of our enemies, Italy and France are economically so hard hit they are only upheld by England's energy and activity. If we can break England's back the war will be at once decided in our favour.’15
Holtzendorff argued that Britain was particularly vulnerable to interdiction of wheat supplies and had at most 8 million tons of merchant shipping available to carry food. This could be sunk at small cost and small risk at a rate of up to 600,000 tons a month for the first four months, and 500,000 tons for each of the following two months. Neutral vessels would be frightened from the seas, reducing available shipping still further, and the crews of German ships interned in neutral ports would scuttle their vessels rather than allow the British to seize them to make up for the tonnage sunk. British shipping would be reduced by 39 per cent within five months. Since the 1916 harvest in the US and in Latin America had proved poor, Britain could be brought to its knees within six to eight months. It was assumed the British would not introduce rationing, since the British national character could not accept its discipline, for ‘the people of England have not been educated to submit to such coercion’.16 The British economy could easily be knocked off course by rising prices. In addition, the British coal industry was dependent upon Scandinavian timber for pit props, and closing off this trade, in turn, would damage the iron and steel industries, rendering Britain incapable of replacing lost ships. Thus, the war could be concluded successfully before the next harvest in the autumn of 1917. US intervention was a risk but one that should not hinder the decision.
The figures had been worked out for Holtzendorff by a number of economic experts drawn from academe and commerce, including Dr Richard Fuss from a Madgeburg-based banking institute and Professor Hermann Levy of the University of Heidelberg. The apparent ability to achieve significant results had also been proven to the navy's satisfaction by the ‘intensified’ submarine campaign from October 1916, which accounted for 757 vessels by January 1917, since the Germans now had over 100 operational U-boats available. All the assumptions, however, were questionable.
Buoyed by American credit, the British economy and people were far more adaptable than supposed. Holtzendorff's advisers failed to take into account cereals other than wheat, the British ability to bring more acreage under cultivation, and the temporary nature of a single bad harvest in the US. Diplomatic necessity compelled the Germans to allow the Scandinavian neutrals to continue to trade commodities with Britain, including timber. The Germans also equated tonnage with cargoes, failing to appreciate that prioritisation of cargoes could offset overall shipping losses. There was little consideration given to possible British countermeasures.
Bethmann-Hollweg, who welcomed the elevation of Hindenburg and Ludendorff, failed to understand that Ludendorff was utterly opposed to any question of compromise. Indeed, the chancellor's enquiry of the military and naval High Commands as to potential bargaining positions in preparation for a peace offer to the Entente, which was announced on 12 December 1916, elicited sweeping statements of war aims. Attempting a conciliatory move, Bethmann-Hollweg suggested he would be prepared to consider introduction of unrestricted submarine warfare if it could ‘outweigh the handicap of America joining our enemies’, but reserved the decision for himself. Hindenburg bluntly replied that he intended ‘with the fullest sense of responsibility for the successful conclusion of the war, to support every effort in the military sphere that I consider to be necessary to that end’.17 Bethmann-Hollweg was further undermined by the Catholic Centre Party's support for an unrestricted campaign, which stripped away his ability to resist the demands of the political right within the Reichstag. Popular support was also assured, the mystique of the U-boats having been fed by a flood of books, verse, propaganda posters and other images since the spring of 1915.
Hindenburg and Ludendorff now fully supported reopening unrestricted submarine warfare, because victory over Romania had freed troops to mask the Netherlands and Denmark should they come into the war. The assumption was that the war could be won before the Americans arrived in sufficient numbers to make any difference. Given the calculation that the United States was already a de facto part of the Entente in economic and even political terms, only an American military presence was considered as an additional consequence, Ludendorff remarking, ‘I don't give a damn about America’.18 Rather similarly, Tirpitz's successor as navy minister, Admiral Eduard von Capelle, proclaimed that American troops would not arrive in Europe as their troopships would be sunk, ‘Thus America from a military point of view means nothing, and again nothing, and for a third time nothing.’19 Hindenburg and Ludendorff were prepared to threaten resignation if unrestricted submarine warfare was not reintroduced.
Arriving at Pless for a conference on 29 December 1916, Bethmann-Hollweg received a less than warm welcome from Hindenburg, while Helfferich, who accompanied him, was barred altogether from participating in the talks. The discussion, however, centred mostly on German General Headquarters (OHL) war aims. One of the naval representatives present, Captain von Bülow, urged Ludendorff to persuade Bethmann-Hollweg to accept unrestricted submarine warfare, but Ludendorff said it was Holtzendorff's task. Holtzendorff meanwhile felt a united naval and military front was needed to force the Kaiser, who had moral scruples with respect to unrestricted submarine warfare, to take the decision against Bethmann-Hollweg. Though not yet aware of Holtzendorff's memorandum, the chancellor had grasped the weakness of his position, his difficulties being compounded by the news on 31 December that the Entente had rejected his peace offer. It was not clear, therefore, how much longer he could hold out.
Holtzendorff finally showed his memorandum to Bethmann-Hollweg on 4 January 1917. Informed that same day by an emissary from Scheer, Captain Magnus von Levetzow, the head of the High Seas Fleet Operations Division, that the navy had lost confidence in his leadership, Holtzendorff then told Hindenburg that he would go direct to the Kaiser to appeal for a decision. Bethmann-Hollweg clung to the rapidly disappearing prospect that he could determine the timetable for the introduction of unrestricted submarine warfare and, summoned by the Kaiser to Pless, asked Holtzendorff to meet him there. Having consulted Hindenburg and Ludendorff, Holtzendorff agreed to delay ordering the commencement of unrestricted operations but, meeting the Kaiser, he outlined his arguments in a manner effective enough to win him over. Holtzendorff, Hindenburg and Ludendorff agreed that the chancellor should be forced to resign if he did not accept unrestricted submarine warfare, and they confronted the Kaiser with their demands on the evening of 8 January. Having been forced previously to umpire the disagreement between his advisers, the Kaiser happily agreed that it was a purely military decision. The wording of his invitation to Bethmann-Hollweg should have sounded the alarm bells: ‘Since my order to the Navy regarding the U-boat war has to go out no later than the day after tomorrow, I shall be delighted to see you here tomorrow.’20 Overnight, Holtzendorff prepared a new memorandum to steel the Kaiser for the coming confrontation.
When Bethmann-Hollweg, suffering from a chill, arrived at Pless on the morning of 9 January, Georg von Müller met him. A serious-minded Saxon, whose nickname of ‘Rasputin’ was a sarcastic comment on his austere nature, Müller had been a sceptic on submarines. However, he had been persuaded by the better than expected German harvest, and evidence of resentment of the British blockade by neutral powers, that it was worth attempting ‘this last shot in our locker’.21 Müller informed the chancellor that all was already settled and asked him not to reject submarine warfare out of hand. Bethmann-Hollweg met Hindenburg and Ludendorff at 11.15 a.m. The chancellor's later account, as expressed to Helfferich and the head of t
he Civil Cabinet, Rudolf von Valentini, differed somewhat from the official record. He had continued to express his reservations, but ineffectively in face of the military and naval arguments put forward and the inescapable fact that there was little prospect of a negotiated peace: having rejected Bethmann-Hollweg's overtures, the Entente was to reject President Wilson's Peace Note of 18 December on the following day. While Bethmann-Hollweg conceded that the chances of success appeared favourable, they were ‘not capable of being demonstrated by proof’. Hindenburg stated, ‘We need the most energetic, ruthless methods which can be adopted.’ Thus, the chancellor agreed to the necessary diplomatic preparations intended to try and keep the Americans from entering the war, remarking that, since the military considered it absolutely necessary, ‘then I am not in a position to speak against it’.22
Helfferich had spent the night of 8–9 January reading through Holtzendorff's original memorandum and wired a rebuttal to Bethmann-Hollweg, arguing for a further delay. The wire only reached Pless in the early afternoon, by which time the chancellor's opposition had entirely collapsed. The Crown Council met at 1800 hours, comprising the Kaiser, Bethmann-Hollweg, Hindenburg, Ludendorff, Holtzendorff, Müller, Valentini and the head of the Military Cabinet, Colonel-General Moriz, Freiherr von Lyncker. It was a foregone conclusion.
According to Valentini, ‘Everyone stood around a large table, on which the Kaiser, pale and excited, leaned his hand.’ Holtzendorff spoke of his confidence in victory ‘in at most six months’ before ‘a single American had set foot on the continent’. Hindenburg observed that he was now ready if the Danes and Dutch entered the war. He also dismissed Bethmann-Hollweg's odd assertion that the Swiss might also come into the war. With ‘a visible inner excitement’, the chancellor again stressed the danger of American intervention, but closed by saying that he would no longer oppose the measure. Müller, who described Bethmann-Hollweg as speaking in a ‘rambling tone’, suggested it was not so much approval but ‘an acceptance of the facts’. The Kaiser, who quoted a newspaper article by a German industrialist supporting submarine warfare, supposedly listened to his chancellor with sympathy, though it seems the Kaiser's actual mood was one of impatience, snorting ‘By God, this man still has scruples’, and declaring that ‘unrestricted U-Boat warfare was therefore decided’. Bethmann-Hollweg retired to his room nursing his cold, telling Müller that Germany would ultimately have to ‘sign an exceedingly modest peace’.23
Helfferich felt Bethmann-Hollweg should have resigned immediately. The chancellor concluded that he should stay to mitigate further military demands, and because he might yet manage to keep the Americans out of the war. His resignation in the face of the overwhelming military, naval and public support for unrestricted submarine warfare would also have required greater moral certainty than the chancellor possessed. Speaking before the Reichstag Finance Committee on 31 January, Bethmann-Hollweg rationalised his capitulation by suggesting that, although it had been indefensible to commence unrestricted submarine warfare, the situation had now changed in Germany's favour and it would be indefensible not to do so. Even Helfferich, appearing before the same committee, now dismissed American intervention, claiming that by the autumn Britain ‘will sprawl like a fish in the reeds and beg for peace’.24
The Kaiser signed the decree authorising the campaign on 19 January 1917, and on 1 February the Germans announced the revival of unrestricted submarine warfare around the British Isles and in the Mediterranean. One American steamer per week would be permitted through the war zone if clearly identified and carrying no contraband. Compared to 1915, there were now 121 U-boats available – of which 41 would always be at sea – with enhanced underwater capabilities and more torpedoes. The leading German technical expert on submarines, Ulrich-Eberhard Blum, had calculated before the war that 222 U-boats would be needed to wage an effective campaign. Nevertheless, a dramatic increase in Entente shipping losses resulted, rising from 464,599 tons in February 1917 to 507,001 tons in March and 834,549 tons in April. The tonnage lost in the first six months of the campaign averaged 643,000 tons a month, close to Holtzendorff's estimates. Other ships were damaged and the sailing of yet others delayed, but the British economy proved resilient.
The impact was sufficient for Jellicoe, now First Sea Lord, to give his support in June 1917 for what became the Passchendaele campaign, as a means of breaking through to the German submarine bases at Ostend and Zeebrugge. In fact, the menace of the submarine was already being blunted for all that pre-war preparations for anti-submarine and anti-mine warfare had been deficient. Technical advances already meant it was possible for naval vessels to survive torpedo attack. Minefields and nets were also used, as in the Dover Barrage, the Northern Barrage between Norway and the Orkneys and the Otranto Barrage in the Adriatic. Dirigibles and aircraft, too, were used for anti-submarine patrols.
The real solution to unrestricted submarine warfare was a revival of the method well known to the age of sail, the convoy. Convoys had been used from the beginning of the war to protect troopships and, in February 1917, were successfully introduced for the coal trade between Britain and France and, in April 1917, for the Scandinavian trade. The Admiralty resisted their general introduction in the belief that the desirable ratio of escorts to merchantmen would be as high as 2:1. Merchant captains also protested that they could not keep station in convoys, which would be reduced to the speed of the slowest ship, and that they would therefore present a wealth of targets. Ships in convoy, it was further argued, would not be able to zigzag as did single ships.
Convoys, however, would prove as hard to locate in the expanse of the sea as single ships, while the concentration of vessels made escort duties easier and increased the opportunities for the escort vessels to engage submarines effectively, and convoys could also be routed away from danger areas. As a result of strong support from the prime minister, David Lloyd George, an experimental convoy was run from Gibraltar to Plymouth on 10 May 1917 without loss. American entry to the war in itself also removed fears of a lack of available escort vessels. By October 1917, a total of 99 homeward-bound convoys had reached harbour safely, and only 10 vessels had been lost. In all, British shipping losses in the last quarter of 1917, of 702,779 tons (235 ships), were only just over half the peak figure of 1,315,496 tons (413 ships) lost in the second quarter of the year. Only three troopships carrying American troops were torpedoed, with only 68 American soldiers killed.
By November 1917 the convoy system was fully operational and U-boats were forced to attack underwater and largely in coastal waters. Escorts were now more successful, using prototype hydrophones and seabed systems to detect U-boats and equally newly developed depth charges, which had accounted for 30 U-boats by 1918. Early sonar had also been developed by this stage. The U-boats also failed to modify their tactics by operating in more than single numbers. Indeed, the submarine campaign might have been more effective had Holtzendorff not repeatedly rejected proposals for creating what in the Second World War would become known as wolf packs, in the vain belief that covering all sea approaches to Britain with individual submarines would force the British to disperse their escort vessels. Construction had barely kept pace with losses, German yards having to compete for manpower and raw materials against other industrial priorities. Of 335 U-boats deployed by the Germans during the war, 178 were lost with 4,474 crew killed.
U-boats still sank 6,394 ships, amounting to 11.9 million tons, between 1914 and 1918, but the decision had been a disastrous one, for the political fall-out in terms of the American entry into the war decisively tipped the balance against Germany. There were other irritants in US–German relations such as German involvement in Mexico, partly contributing to an American occupation of Vera Cruz between April and November 1914, and to American involvement in Mexico's incipient civil war. There was also some attempted German subversion in the US itself, the most serious of 88 suspicious incidents or accidents being an explosion at Black Tom Island, New Jersey, in July 1916, which de
stroyed $20-million worth of ammunition destined for the Entente and killed three people. The temperature of Anglo-American relations had been similarly raised by the British suppression of the Easter Rising in April 1916, though other events had also contributed. There was continuing British bending of international maritime law. There was also the continuing rejection of Wilson's mediation efforts as epitomised by Lloyd George's interview with Roy Howard of the American United Press, published in The Times on 29 November 1916, in which the new prime minister indicated his intention of delivering a ‘knock-out blow’ to Germany, and fighting ‘to the finish’. Wilson was convinced that he could only keep America out of the war by ending it, hence his increased efforts at mediation in the winter of 1916–17.
The Making of the First World War Page 18