"Before the war, Germany had devoted considerable study to the damaging blows which could be made against Britain through attacking the vital trade routes. It was, however, fully appreciated that the task of getting through to the Atlantic, and so to the other highways, would always be difficult when once hostilities had begun.
There were but two methods practicable. If one of her regular naval cruisers attempted to burst through the blockade by force, she would be handicapped from the first: she would be too blatant, too obvious. For, whilst a merchantman can become a disguised warship, it is not always possible to change the appearance of a man-of-war in order to make her resemble a passenger or cargo vessel. (It is true that during the war two or three of the British naval sloops were altered to suggest traders, but they were not a great success and did not always deceive the enemy.) When a cruiser has four, or even three funnels, war-like bow, low freeboard, and conspicuous guns, but a forebridge without any of the high decks of a liner, no amount of paint can fool a seafarer into believing her innocence. Therefore the chances of genuine cruisers running the blockade were rightly considered remote. We have seen that Kaiser Wilhelm der Grosse and Berlin succeeded because the blockade patrols were not yet of sufficient strength, and these two raiders went hundreds of miles out of their way. But they were also dressed to conceal their true character, prepared to pretend and bluff; and this second method quite definitely was accepted by the German Admiralty as the only means of sending surface cruisers forth when the other genuine cruisers had ceased to exist.
It remains an interesting fact that not one of the latter throughout the whole four years made the slightest effort, either independently or in company, to rush the Dover Straits or get westward of Scotland. At the time when the Canadian convoy was coming over the Atlantic there certainly were both anxiety and a half-expectation at the British Admiralty that German battle-cruisers might break through and do their direst. It would have been a gamble, but certainly a justifiable risk. Transports full of soldiers are always most attractive targets in their helplessness; and it would have been of direct assistance to the German Army if some thousands of British troops could have been shelled or drowned. Whether all the battle-cruisers would have got back to Germany again is quite another consideration…"
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