While the atomic bombs used by the US in WWII succeeded in requiring the unconditional surrender of Japan, the decision to use such weaponry was made in an irresponsible manner because of the civilian populations killed, and because Japanese surrender was already in progress.    

Historical Context: WWII and Nuclear Weapons

There was a lot going on in the 1940's and years leading up to the bombing of Japan both in America and Internationally.  Most importantly, WWII was being fought by many nations around the globe.  Although many countries were involved, the war was fought by two sides or groups of countries, the Axis vs. the Allies.  The Axis, or aggressors of WWII, consisted of Nazi Germany, the Empire of Japan, and Italy.  Each country entered wars with individual intentions, but eventually made the Tripartite Pact.  The Allied forces were originally led by the United Kingdom and France, and entered the war due to their commitment to Poland after they were invaded by Germany.  More countries joined the Allies as Germany and Japan continued to invade countries.  Regardless of hostility towards Poland, the Soviet Union was later accepted into the Allies, as well as the US in 1941 after the bombing of Pearl Harbor.  

"Yesterday, December 7, 1941 - a date which will live in infamy - the United States of America was suddenly and deliberately attacked by naval and air forces of the Empire of Japan."  Franklin Delano Roosevelt

FDR signing war declaration on Japan.
Declaration to war speech December 8th, 1941

Japan had intentions to militarily expand for resources in the 1930's and 40's.  Japan was becoming an international threat as it conquered its neighboring southeast asian countries of China, Malaya, Burma, Singapore, and the Philippines.  By taking control of other countries, Japan was capable of intercepting and controlling trade routes crucial for enemy supplies and resources.  Upon deciding that further expansion would require war with US, Japan bombed Pearl Harbor.  
'USS SHAW exploding during the Japanese raid on Pearl Harbor.' December 7, 1941.
Headlines in Tokyo December 8th, 1941

A Wicked Invention, Atomic Weapons

During this time of international unrest, scientists around the world were experimenting with the splitting of atoms.  In 1938 just before the outbreak of WWII German physicists discovered that a neutron could cause the nucleus of an Uranium atom to split (fission.)  Experimenting scientists of other countries later determined that the energy released by splitting an atom is 100 times greater than that released by a chemical reaction per atom.  
Scientists that were able to escape the Nazi regime feared that Hitler would pursue a bomb created by the splitting of an Uranium atom.  Albert Einstein, a famous scientist of the time, wrote to president FDR to express his concern of Germany's capability of creating an atom bomb, and suggested that we create one first.   

By: Hayden Loch