Happy Birthday, Superman - Or, as the new Man of Steel trailer would have it, "Su[insert distracting noise]."
Today marks the 75th anniversary of the Last Son of Krypton, who has been fighting crime and saving his adopted world simply because that's the way he was raised. (Good work on that one, Ma and Pa Kent). But while Clark Kent's alter-ego has been a constant presence in comic books, movies and on television for the last seven and a half decades, he hasn't been constant in terms of characterization. Throughout his existence, Superman has changed to match the times, for better and worse.