The statement that best analyzes why President Truman decided to abandon the plan to launch an amphibious invasion of Japan in 1945 is:
Truman realized that the invasion would cost too much money and American lives.
This reflects the significant concerns within the U.S. government regarding the estimated high casualties associated with a mainland invasion of Japan, which played a prominent role in Truman's decision-making process. The use of atomic bombs was seen as a means to achieve a quicker end to the war while potentially saving lives compared to a prolonged invasion.