The Battle of Britain Five Months That Changed History, May—October 1940 by James Holland (z-lib.org).epub

defensive measures to guard against it.’ This was the nub of the matter. The
Home Fleet did not have enough ships to both keep vigil in the Channel and
adequately protect convoys as they drew towards the Western Approaches.
Forbes believed that it made far more sense for the Germans to try and
sever the transatlantic lifelines than attempt an invasion. In any case, he was
certain that until the RAF had been destroyed, no invasion attempt could
possibly be made without Britain knowing about it at least twenty-four
hours earlier, thanks to radio intercepts and aerial reconnaissance of
Continental ports. Should such an attempt be spotted, ships could hurry to
the Channel in time. In the meantime, he believed his forces were far better
used protecting convoys from U-boats and sweeping for mines.
Pound, however, was having none of it. Despite the calm logic of
Forbes’s arguments, the First Sea Lord declared them unconvincing. ‘The
JIC have appreciated that the enemy has plenty of military forces available
for invasion,’ he noted tersely, ‘in addition to his other commitments.’
Even Pound, however, must have been troubled by the staggering
numbers of ships that were now being sunk. Every week the Chiefs of Staff
and Cabinet were presented with a list of shipping that had been lost; it
made for sobering digestion. In the last week of June, for example, so much
shipping had been sent to the bottom of the sea, it could no longer fit on the
graph summaries that were produced by the Naval Intelligence Department.
From 288,461 tons of shipping lost in May, the figure had risen to 585,496
tons in June. Since the beginning of the war, nearly 1.5 million tons of new
shipping had been built but nearly 2.1 million tons had been sunk. At
current rates, that discrepancy would soon rise to critical proportions.
Strangling British sea-lines had suddenly become a very real possibility –
particularly if the German U-boat force continued to grow.
When the then Kapitän Karl Dönitz had been appointed commander of the
Kriegsmarine’s submarine force in 1935, he had been disappointed by the
post. A naval agreement had just been signed between Britain and
Germany, in which Germany had suggested limiting her naval strength to
35 per cent of that of Britain. It was a clever move, because it tested
whether Britain was prepared to move away from the Versailles Treaty,
whilst suggesting that Germany had no hostile intentions towards her. At
the same time, because of the large size of the Royal Navy, 35 per cent still
enabled Germany to build two large battle cruisers, the Gneisau and