Seventy years later, it is widely believed that President Harry S. Truman made a decision to authorize the bombings of Hiroshima and Nagasaki. The truth, writes William Johnston in the Hartford Courant, is that he never did, at least not explicitly. Johnston, professor of history, professor of East Asian Studies, examines in an op-ed how history has been rewritten surrounding the bombings. In fact, Truman's first explicit decision about atomic bombs was to later order that their further use be stopped without his "express authority." But in summer 1946, Johnston explains, the need arose to write an alternative narrative, as the bomb's…