secretary of war, wrote in his diary that the president was “a simple man, prone to make up his mind quickly and decisively, perhaps too quickly—a thorough American.” This was not a great president, “not distinguished at all . . . not Lincolnesque, but an instinctive, common, hearty-natured man.” Men as different as McCloy, Rabi and Oppenheimer all thought Truman’s instincts, particularly in the field of atomic diplomacy, were neither measured nor sound—and sadly, certainly were not up to the challenge the country and the world now faced.
