Germany declared war on the United States on 11 December 1941, four days after the attack on Pearl Harbor.
1941年12月11日，珍珠港事件四天后，德国向美国宣战。
'So we had won after all!... England would live, Britain would live; the Commonwealth of Nations and the Empire would live...', reflected Churchill.
丘吉尔的反应是："我们终将成功！……英格兰必胜，不列颠必胜，英联邦和英帝国必胜……"
But the first effects were disastrous for Britain.
但是，第一个影响对英国来说是灾难性的。
The Pacific drew off the American naval vessels which had protected the convoys.
美国海军抽调一部分力量到太平洋，无力再应对英国的护航问题了，
And it proved to be an even tougher job selling intelligence to the US Navy than it had been in the British Admiralty.
而且，与美国的情报交流非常有障碍。
Naval Enigma information had indicated the operation of fifteen U-boats off the American coast at the declaration of war, but the warning had been spurned, and no precautions taken.
在宣战发生时，海军谜机的破译表明，有15艘U型潜艇正在美国海岸行动，但美军对此不屑一顾。
Enormous shipping losses marked an unhappy start to the Grand Alliance.
大量的船只损失，使同盟的笑容开始消失。
Then on 1 February 1942, a far greater blow was dealt.
接着在1942年2月1日，又发生了更大的灾难。
The U-boats switched over on to a new Enigma system.
U型潜艇转而用了新的谜机系统。
The Bombes failed to deliver their prophecies.
炸弹机无法成功破解它们。
There was no more ULTRA.
没有比这更糟糕的事了。
The black-out of February 1942 meant that the U-boat Enigma analysis had to begin all over again, with the past two years serving as warming-up practice.
1942年2月的中断意味着，潜艇谜机的分析工作必须重头再来了，过去两年都只能算热身。