What choices did Truman struggle with in the summer of 1945?

Do we drop the atomic bombs on the Japanese, or lead a offensive on the beachs of japan. (He later chose to drop the atom bombs, to save american lives.)

He had two choices. Either he would drop the atomic bombs onto Japan and end the war immediately with severe losses on the Japanese side, or he would continue with a blockade and a beach invasion on Japanese territory. He decided to use nuclear weapons instead of sending soldiers to Japan because of a statistical analysis which claimed that more lives would be lost through an invasion than through usage of nuclear weapons.