Editing Attack on Pearl Harbor (section)

===Japanese declaration of war===
{{See also|Japanese war crimes}}

The attack took place before any formal declaration of war was made by Japan, but this was not Admiral Yamamoto's intention. He originally stipulated that the attack should not commence until thirty minutes after Japan had informed the United States that peace negotiations were at an end.<ref>{{Cite news |url=https://www.historyonthenet.com/when-was-pearl-harbor/ |title=When was Pearl Harbor? |date=2014-11-26 |work=History |access-date=2018-08-17 |archive-date=August 17, 2018 |archive-url=https://web.archive.org/web/20180817161358/https://www.historyonthenet.com/when-was-pearl-harbor/ |url-status=live}}</ref> However, the attack began before the notice could be delivered. Tokyo transmitted the 5000-word notification (commonly called the "14-Part Message") in two blocks to the Japanese Embassy in Washington. Transcribing the message took too long for the Japanese ambassador to deliver it at 1:00{{spaces}}p.m. Washington time, as ordered, and consequently the message was not presented until more than one hour after the attack had {{nowrap|begun{{hsp}}{{mdash}}}}{{hsp}} but American code breakers had [[Purple cipher|already deciphered]] and translated most of the message hours before it was scheduled to be delivered.{{sfn|Toland|1983}}<ref name=codebreakers>{{cite book |last1=Kahn |first1=David |title=The Codebreakers: The Comprehensive History of Secret Communication from Ancient Times to the Internet |date=1996 |publisher=Simon and Schuster |isbn=978-1-4391-0355-5}}</ref>{{rp|pp.2ff}} The final part of the message is sometimes described as a declaration of war. While it was viewed by a number of senior American government and military officials as a very strong indicator negotiations were likely to be terminated{{sfn|Prange|Goldstein|Dillon|1981|pp=424, 475}} and that war might break out at any moment,{{sfn|Prange|Goldstein|Dillon|1981|pp=493–494}} it neither declared war nor severed diplomatic relations. [[Japanese declaration of war on the United States and the British Empire|A declaration of war]] was printed on the front page of Japan's newspapers in the evening edition of December 8 (late December 7 in the United States),<ref>{{cite web |mode=cs2 |author=Emperor of Japan Hirohito |date=December 8, 1941 |title=Declaration of War against the United States and Britain |url=https://www.gilderlehrman.org/sites/default/files/inline-pdfs/T-01415_0.pdf |access-date=December 10, 2021 |archive-url=https://web.archive.org/web/20210715210137/https://www.gilderlehrman.org/sites/default/files/inline-pdfs/T-01415_0.pdf |archive-date=July 15, 2021 |url-status=live |via=[[Gilder Lehrman Institute of American History]]}}</ref> but not delivered to the American government until the day after the attack.

For decades, [[conventional wisdom]] held that Japan attacked without first formally breaking diplomatic relations only because of accidents and bumbling that delayed the delivery of a document hinting at war to Washington.<ref>{{Cite news |mode=cs2 |last=Sterngold |first=James |date=November 21, 1994 |title=Japan Admits It Bungled Notice of War in '41 (Published 1994) |work=The New York Times |url=https://www.nytimes.com/1994/11/21/world/japan-admits-it-bungled-notice-of-war-in-41.html |access-date=December 1, 2020 |issn=0362-4331 |archive-date=December 10, 2020 |archive-url=https://web.archive.org/web/20201210000317/https://www.nytimes.com/1994/11/21/world/japan-admits-it-bungled-notice-of-war-in-41.html |url-status=live}}</ref> In 1999, however, Takeo Iguchi, a professor of law and international relations at [[International Christian University]] in Tokyo, discovered documents that pointed to a vigorous debate inside the government over how, and indeed whether, to notify Washington of Japan's intention to break off negotiations and start a war, including a December 7 entry in the war diary saying, "[O]ur deceptive diplomacy is steadily proceeding toward success." Of this, Iguchi said, "The diary shows that the army and navy did not want to give any proper declaration of war, or indeed prior notice even of the termination of negotiations{{spaces}}... and they clearly prevailed."<ref>{{cite news |url=https://www.nytimes.com/1999/12/09/world/pearl-harbor-truly-a-sneak-attack-papers-show.html |title=Pearl Harbor Truly a Sneak Attack, Papers Show |author=Howard W. French |newspaper=The New York Times |date=December 9, 1999 |access-date=February 14, 2017 |url-status=live |archive-date=December 5, 2016 |archive-url=https://web.archive.org/web/20161205202932/http://www.nytimes.com/1999/12/09/world/pearl-harbor-truly-a-sneak-attack-papers-show.html}}</ref><ref>{{cite news |mode=cs2 |last=Kawabata |first=Tai |date=December 9, 2014 |title=Historian seeks to clear embassy of Pearl Harbor 'sneak attack' infamy |newspaper=[[The Japan Times]] |url=https://www.japantimes.co.jp/news/2014/12/09/national/history/historian-seeks-to-clear-embassy-of-pearl-harbor-sneak-attack-infamy/ |url-status=live |archive-url=https://web.archive.org/web/20210516225555/https://www.japantimes.co.jp/news/2014/12/09/national/history/historian-seeks-to-clear-embassy-of-pearl-harbor-sneak-attack-infamy/ |archive-date=May 16, 2021}}</ref>

In any event, even if the Japanese had decoded and delivered the 14-Part Message before the beginning of the attack, it would not have constituted either a formal break of diplomatic relations or a declaration of war.<ref>{{harvnb|Prange|Goldstein|Dillon|1981|p=485}}. "[The] fourteenth part was not a formal declaration of war. It did not even rupture diplomatic relations. It merely broke off the discussions."</ref> The final two paragraphs of the message read:<ref>{{cite web |mode=cs2 |date=December 7, 1941 |title=Japanese 'Fourteen Part' Message of December 7, 1941 |type=Memorandum |via=HyperWar Foundation |url=https://www.ibiblio.org/hyperwar/PTO/Dip/Fourteen.html |access-date=December 10, 2021 |archive-url=https://web.archive.org/web/20170917001957/http://www.ibiblio.org/hyperwar/PTO/Dip/Fourteen.html |archive-date=September 17, 2017 |url-status=live}}</ref>

{{blockquote| Thus the earnest hope of the Japanese Government to adjust Japanese-American relations and to preserve and promote the peace of the Pacific through cooperation with the American Government has finally been lost.{{parabr}}The Japanese Government regrets to have to notify hereby the American Government that in view of the attitude of the American Government it cannot but consider that it is impossible to reach an agreement through further negotiations.}}

United States naval intelligence officers were alarmed by the unusual timing for delivering the {{nowrap|message{{hsp}}{{mdash}}{{hsp}}}}1:00{{spaces}}p.m. on a Sunday, which was 7:30{{spaces}}a.m. in {{nowrap|Hawaii{{hsp}}{{mdash}}{{hsp}}}}and attempted to alert Pearl Harbor. But due to communication problems the warning was not delivered before the attack.<ref name=codebreakers/>{{rp|Ch. 1}}