Baseball has witnessed more than 125,000 home runs. Many have altered the outcome of games, and some have decided pennants and become legend. But no dinger has had greater impact than Hank Aaron's 715th home run. His historic blast on April 8, 1974, lifted him above Babe Ruth on the all-time list, an achievement that shook not only baseball but our nation itself. Aaron's magnificent feat provoked bigotry and shattered prejudice, inspired a generation,...