And if "the Bomb" was so overpowering and decisive, as immediately claimed by US propaganda, then why did the US attack again on Aug 14/15, using pumpkin bombs¹, in a " Grand Finale" ?

Here's Yozo Kudo, general secretary of the Japanese National Association for the Assessment of Air Raids and War Damage:

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INTERVIEW: Why U.S. air raids continued until day of Japan’s surrender — THE ASAHI SHIMBUN² — August 14, 2023 — Yozo Kudo, 73, secretary-general of the national association of groups recording air raids and war damage

The United States carried out air raids from Aug. 14 to early Aug. 15. More than 1,000 aircraft, including 825 B-29 bombers, attacked targets nationwide. It is believed to be the largest number of aircraft deployed for (a string of) air raids during the Pacific War.

Q: Which cities were attacked?

A: Targets included Osaka, where Osaka Arsenal and Kyobashi Station were bombed, Akita’s Tsuchizaki district, Isesaki in Gunma Prefecture, Kumagaya in Saitama Prefecture, and Iwakuni and Hikari in Yamaguchi Prefecture.

When small-scale bombings are included, about 30 locations were attacked. Many people were killed. But casualty counts vary, and the exact number is unknown.

Q: Why were air raids conducted on the day of the surrender or the day before?

A: Japan’s delay in accepting the Potsdam Declaration was in the background.

The government informed the Allied powers on Aug. 10 that it would accept the declaration on condition that the emperor’s rights of sovereignty would not be changed. But arguments within the government and military became tangled over a response from the Allied powers. Some said the emperor’s status was not guaranteed, and an agreement was not reached for some time.

The United States on Aug. 10 stopped air raids on urban areas by B-29 bombers to prevent an adverse impact on peace negotiations. The following day, air raids by B-29 bombers were suspended altogether.

The United States once waited for an end of peace negotiations, although it continued some air raids by other bombers. But Japan did not produce its conclusion for some time, and the United States decided to carry out large-scale air raids on Aug. 14-15 to urge Japan to accept the Potsdam Declaration.

Henry Arnold, commander of the U.S. Army Air Forces, had wanted the grandest possible finale, according to a history of warfare by B-29 bombers.

The U.S. military initially considered an air raid on Tokyo, which would have a strong psychological impact on the Japanese government, but eventually decided to target several areas outside Tokyo.

Japan decided to accept the Potsdam Declaration at a meeting in the presence of the emperor on Aug. 14. But it took time before U.S. military officials on the ground were informed of Japan’s decision, and air raids continued until the early hours of Aug. 15.

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That doesn't give a clear answer as to the motivation of these anewed US terror bombing raids against civilians. There is no military reason, as with all previous attacks on civilians. Just sadism? Or maybe the raids on Hiroshima and Nagasaki were not impressive enough?

1 https://de.wikipedia.org/wiki/509th_Composite_Group

2 https://www.asahi.com/ajw/articles/14980968

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