It ended the war.

It demonstrated in no uncertain terms that waging the kind of war that Japan had waged on China, on England, on the United States, on Burma, on Indonesia, in the Phillipines and Southeast Asia, was to be a thing of the past.

It ended the worship of the Emperor of Japan as a god.
It ended the military domination of the government of Japan.

It forestalled further Soviet penetration into Japan.

It spared the lives of millions of American soldiers who would have been in on the invastion of the home island.

It spared the lives of millions of Japanese soldiers and citizens who would have been inducted into the Japanese defense of the home island.

The atomic bomb was the equivalent of two thousand-plane raids. Conventional attacks were in the ballpark of this amount of carnage as the firebombing of Tokyo will testify.

The use was of the atomic bomb was discussed and debated from the scientific community to the top levels of the government of the US.

The fact that we debate the issues to this day is a credit to the willingness of the participants to live by, review, and listen to the judgement of others after the fact.

Many of us who are the children of vets regard our existence as an outcome of the use of the two atomic bombs.

The use of the bomb as a weapon was justifiable.
The damage of the bomb was terrible.
It should be reviewed, it should be discussed, and the lessons we learn should be up for review as long as humans think of making war.

The United States owes no apology regarding the use of atomic weapons.

Remember, it took more than one. (We had three).

It ended the war.