Great Britain's Sea Policy by Gilbert Murray

I pass to a real difficulty, where I do not feel at all sure that our policy was wise, though on the whole the balance of well-informed opinion seems to approve of it. I mean the so-called total "blockade" of Germany, including the shutting out of foodstuffs. The history of this policy is as follows.

On February 4, 1915, the Germans announced that all the seas round Great Britain were a "war-area" in which they would sink without warning all ships whatsoever. (Neutrals might be spared on occasion, but could not complain if they were sunk.) This was a proposed blockade by submarine, which has hitherto proved to be impracticable. If Germany had commanded the seas she would, of course, have proclaimed a real blockade and prevented any ship from reaching Great Britain.