李海上將是反對使用原子彈的；但是他的出發點是使用原子彈對促使日本無條件投降沒有幫助

http://www.doug-long.com/leahy.htm

Leahy believed the atomic bomb would probably not work. After the atomic bombings of Japan, Leahy condemned the use of the atomic bomb for practical reasons:

• "It is my opinion that the use of this barbarous weapon at Hiroshima and Nagasaki was of no material assistance in our war against Japan. The Japanese were already defeated and ready to surrender because of the effective sea blockade and the successful bombing with conventional weapons." (William D. Leahy, I Was There, pg. 441).