Who said all our great presidents were leaders of thought at times when certain historic ideas in the life of the nation had to be clarified?

Explanation:

The Presidency is not merely an administrative office. That’s the least of it. It is more than an engineering job, efficient or inefficient. It is pre-eminently a place of moral leadership. All our great Presidents were leaders of thought at times when certain historic ideas in the life of the nation had to be clarified.

nuclear fission produces the atomic bomb, a weapon of mass destruction that uses power released by the splitting of atomic nuclei the fighting in iwo jima and okinawa affected the allies' pacific strategy because truman decided to drop the atomic bomb on mainland japan.

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