Why was the atom bomb important?

Answer 1

The biggest reason was that with its use and the ultimate surrender of Japan as a result, it brought a rapid close and end to WWII. Though the Soviet Union's declaration of war against Japan, along with the recent defeat and surrender of Axis allies Germany and Italy were also factors, the bombs were really what drove them to surrender.

The Manhattan Project (codename for the Atom Bomb program) had been in development for several years, and by the time it was nearing testing phase Germany and Italy had already surrendered. However, military plans for the full-scale invasion of Honshu, the Japanese main island, had already been underway for for many months. This plan was known as Operation Downfall.

Military planners for Operation Downfall did not know about the existence of the Manhattan Project or the atomic bomb, as it was known to very few outside the project itself (even Vice President Harry Truman didn't know about it until he became President upon President Franklin Roosevelt's death). Consequently, it was not taken into account during the invasion planning process; even if they had known, it still wouldn't have altered anything, as there was no guarantee the Manhattan Project would succeed or that any subsequent bombs would be ready in time for the invasion.

The primary focus of the invasion was to force the surrender of Japan as quickly as possible, with the fewest casualties inflicted or taken on either side. In the end, this viewpoint was what President Truman used in his decision to use the the atomic bombs on Japan. Though only 2 were used, there were more in production to support an invasion if Japan had not surrendered.

Allied experience fighting the Japanese had made it clear that they would not give up willingly or easily. Intelligence gained at the time (the United States had long since broken the Japanese codes) told the Allies that Japanese military leaders were preparing the entire Japanese population, women and children included, for a full-scale fight to the death should such an invasion occur. Estimates of wounded and dead casualties for both sides were in the multimillion range.

Fighting the Japanese was hard enough on Guadalcanal, Peleliu, the Solomon Islands, the Philippines, China, and elsewhere, but fighting them on their own outer islands of Iwo Jima and Okinawa was much different. Due to the prevailing Bushidocode amongst the Japanese military and many civilians ("Way of the Warrior", or the Samurai code), the Japanese were willing to do anything to defend their home islands and keep from being captured.

At the Battle of Iwo Jima, 21,000 Japanese soldiers were present at the start of the battle; over 20,000 were killed, or committed suicide rather than be captured. At the Battle of Okinawa, about 95,000 Japanese were killed or committed suicide; on the Allied side, over 50,000 Allies killed or wounded.

The Japanese weren't stupid; they knew based on Honshu's geography the best possible invasion strategy for the Allies, and were able to adjust their defenses accordingly. Any full-scale invasion of Honshu and the other home islands of Japan would have been very long, bloody, costly, and demoralizing on all sides.

When the first 2 bombs became operational (Fat Man & Little Boy) President Truman weighed all options, but heaviest on his mind was the estimated cost in lives on both sides an invasion would have produced. Of lesser consideration was the fact that the Manhattan Project had cost millions (a lot back then); to produce a working weapon and not use it during those times would've been politically costly as well. It's important to remember that Pearl Harbor, Bataan, Wake Island, and the other losses inflicted by the Japanese in the Pacific Theatre were still fresh in America's mind, as well as her Allies; payback was first on everybody's priority list.

Although there has been much "revisionist history" that paints the people of Hiroshima and Nagasaki as victims of an unprovoked nuclear attack, nothing is further from the truth. The U.S. Government warned the Japanese governmentabout the weapon's capability and its destructive potential before it was used; twice they refused to surrender. It was only after the second bomb was dropped and they received pictures and reports of the utter devastation that it was finally realized by the Japanese leadership that if they didn't surrender, they'd have no country left to defend. The U.S. already had several other bombs on Tinian Island staged and ready to drop on Japan had the Japanese leadership not finally surrendered.

In the end, the death toll from both cities was in the hundred thousand range or more. When considering the many millions of lives on both sides that would have been needlessly wasted had the bombs not been used, it is apparent that the decision to use the bombs was the right one, for those times, and those circumstances. The sacrifice of those people literally saved their country and their people from an invasion that would have certainly cost much more, and prolonged an already devastating war that had taken the lives of many millions on both sides.

The actual invasion plans for Japan still exist as historical documents, and I've added a link to it below.

Answer 2

It ended WW2 quickly, saving many more lives on both sides than died in the two bombings.

Answer 3

It ended the war.