unhistorical:

August 9, 1945: An atomic bomb is dropped on Nagasaki.

Three days after the bombing of Hiroshima, a second atomic bomb - “Fat Man” - was detonated over Nagasaki, the third detonation of such a weapon in history. After the bombing of Hiroshima, Harry Truman delivered another message of warning to Japan, saying:

If they do not now accept our terms, they may expect a rain of ruin from the air, the like of which has never been seen on this earth.

Between the August 6 bombing and Japan’s surrender, approximately six million propaganda leaflets were dropped over dozens of Japanese towns. Nagasaki, like Hiroshima, was chosen for its military importance - it was a seaport and an industrial center, and it was also home to around 200,000 people. Of these, an estimated 39,000 were killed in the initial bomb blast, and thousands more died later from injuries and exposure to radiation. The temperature of the blast reached 3,900 °C. 

Other atomic bombs were prepared for further attacks, but Japan surrendered (via radio broadcast) on August 15, six days later.