News of the attack on Pearl Harbor reached London first. Realising that Roosevelt would go through the formal process of asking the
United States Congress for a
declaration of war, Churchill began preparing to deliver Britain's own declaration of war immediately after Congress had formally declared war. After learning British territory had also been attacked, Churchill decided there was no need to wait for Congress to act and promptly summoned
Mamoru Shigemitsu,
Ambassador of Japan to the United Kingdom.
Foreign Secretary Anthony Eden was in transit to Moscow at the time, so Churchill was in charge of the
Foreign Office. Churchill instructed Shigemitsu to inform his government that a state of war existed between the two countries and drafted a letter to inform the ambassador of this. Of the letter, Churchill later wrote: "Some people did not like this ceremonial style. But after all when you have to kill a man it costs nothing to be polite." The United Kingdom declared war on Japan nine hours before the United States. The earlier declaration by the British was due to their attacks on the colonies of
Malaya,
Singapore, and
Hong Kong, and also due to the fact that they lacked the American constitutional tradition of requiring the consent of their own national legislature to declare war – the British cabinet could declare war without consulting
Parliament, and could therefore act more quickly.
Churchill's letter The text of Churchill's letter to Shigemitsu is as follows: ==See also==