While no act of war is necessary, it could be argued that dropping the bomb did end the war immediately; otherwise it could have been some time before an end was reached and more lives may have been lost.
No, because it ended the war and saved millions of Japanese lives and Allied Forces lives by preventing the invasion of Japan. It also saved Russian lives by preventing Stalin's forces from invading Japan.
President Truman authorized dropping the Atomic Bomb on Japan to end WWII without invading the Japanese main islands. Invading would have resulted in a massive loss of life on both sides. This is a very controversial subject with valid arguments for and against invasion presented by each side. I recommend that you study this before determining your feelings on the subject.
The atomic bombs were dropped in Japan because Japan had refused to surrender.
After firebombing 67 Japanese cities, on July 26, 1945, the US called for Japan to surrender with the Potsdam Declaration. Japan ignored that request. Then on August 6, the US dropped an atomic bomb on Hiroshima, and on August 9, on Nagasaki. Six days later, on August 15, Japan announced surrender and on September 2, 1945 Japan signed the Instrument of Surrender, ending the war (Germany had signed an Instrument of Surrender on May 7, 1945).
In a 1986 study, historian and journalist Edwin P. Hoyt nailed the "great myth, perpetuated by well-meaning people throughout the world," that "the atomic bomb caused the surrender of Japan." In Japan's War: The Great Pacific Conflict(p. 420), he explained:
"The fact is that as far as the Japanese militarists were concerned, the atomic bomb was just another weapon. The two atomic bombs at Hiroshima and Nagasaki were icing on the cake, and did not do as much damage as the firebombings of Japanese cities. The B-29 firebombing campaign had brought the destruction of 3,100,000 homes, leaving 15 million people homeless, and killing about a million of them. It was the ruthless firebombing, and Hirohito's realization that if necessary the Allies would completely destroy Japan and kill every Japanese to achieve "unconditional surrender" that persuaded him to the decision to end the war. The atomic bomb is indeed a fearsome weapon, but it was not the cause of Japan's surrender, even though the myth persists even to this day."
In a trenchant new book, The Decision to Drop the Atomic Bomb (Praeger, 1996), historian Dennis D. Wainstock concludes that the bombings were not only unnecessary, but were based on a vengeful policy that actually harmed American interests. He writes (pp. 124, 132):
... By April 1945, Japan's leaders realized that the war was lost. Their main stumbling block to surrender was the United States' insistence on unconditional surrender. They specifically needed to know whether the United States would allow Hirohito to remain on the throne. They feared that the United States would depose him, try him as a war criminal, or even execute him ... Unconditional surrender was a policy of revenge, and it hurt America's national self-interest. It prolonged the war in both Europe and East Asia, and it helped to expand Soviet power in those areas. General Douglas MacArthur, Commander of US Army forces in the Pacific, stated on numerous occasions before his death that the atomic bomb was completely unnecessary from a military point of view: "My staff was unanimous in believing that Japan was on the point of collapse and surrender." General Curtis LeMay, who had pioneered precision bombing of Germany and Japan (and who later headed the Strategic Air Command and served as Air Force chief of staff), put it most succinctly: "The atomic bomb had nothing to do with the end of the war.
Source: Weber, Mark "Was Hiroshima Necessary? Why the Atomic Bombings could have been avoided" The Journal of Historical Review, May-June 1997 (Vol. 16, No. 3), pages 4-11.
August, 1945. On August 6, 1945 an atomic bomb was dropped on Hiroshima, 3 days
later one was dropped on Nagasaki. On August 14, 1945 the Japanese surrendered.
The US President Harry Truman.
The reason was to end the war with Japan .
President Truman got the order to use them against Japan.
truman
Harry S. Truman decided to drop the atomic bomb on Japan during World War II.
The reason was to end the war with Japan .
End the war with japan and to scare the Soviets.
Force them to surrender as soon as possible.
Harry Truman drop the Atomic Bomb on Hiroshima, Japan and Nagasaki, Japan.
To end the war with Japan .
Truman
Harry s. truman approved the dropping of an atomic bomb on japan.