Many Americans approved of the use of atomic weapons on Japan despite their destructive power because

they believed it would shorten the war and ultimately save American lives

they were eager to see if this new technology was effective in preventing wars

they believed that the atom bomb would cause no more damage than regular bombs

they were told that it was the only certain way to defeat the militant Japanese empire

They believed it would shorten the war and ultimately save American lives.

Explanation:

President Harry Truman justified the use of bombs on Hiroshima and Nagasaki at the end of World War II by explaining to the American people that this attack would actually save lives. Truman's advisors predicted that a land invasion of Japan, similar in size to the invasion complete in Normandy, would result in hundreds of thousands of casualties for the United States and the Japanese.

However, the bombing would only target two cities and would ultimately kill less citizens. Many Americans approved of this reasoning and thought the use of the atomic weapons was reasonable.

Your answer will be A.) they believed it would shorten the war and ultimately save American lives

Explanation:

President Truman thought that if they invaded Japan they would lose so much more than a war they would lose thousands of American lives.