The most enduring American hero of the last century is someone who lived half his life in disguise and the other half as the world's most recognizable man. He is not Jack Kennedy or Joltin' Joe DiMaggio, Batman or Jerry Seinfeld, although all of them were inspired by him. It was on his muscle-bound back that the iconic comic book took flight and that the very idea of the superhero was born. He appeared on more radio broadcasts than Ellery Queen and in more movies than Marlon Brando, who once pretended to be his father. He helped give America the backbone to wage war against Adolph Hitler, the Great Depression, and the Ku Klux Klan. He remains an intimate to kids from Boston to Belgrade and has adult devotees who, like Talmudic scholars, parse his every utterance. And he has done it all with an innocence and confidence that let him appear publicly with underpants over full-body tights and assume an alter ego who kept pursuing the prettiest girl in town even though he seldom got her.

The most enduring American hero is an alien from outer space who, once he reached Earth, traded in his foreign-sounding name Kal-El for a singularly American handle: Superman. So what is it about Superman, I wondered, that has let him not just survive but thrive for seventy-four years and counting?

It starts with the intrinsic simplicity of his story. Little Orphan Annie and Oliver Twist remind us how compelling a foundling's tale can be, and Superman, the sole survivor of a doomed planet, is a super-foundling. The love triangle connecting Clark Kent, Lois Lane, and Superman has a side for everyone, whether you are the boy who can't get the girl, the girl pursued by the wrong boy, or the conflicted hero. He was not just any hero, but one with the very powers we would have: the strength to lift boulders and planets, the speed to outrun a locomotive or a bullet, and, coolest on anyone's fantasy list, the gift of flight.

Superpowers are just half the equation. More essential is knowing what to do with them, and nobody has a more instinctual sense than Superman of right and wrong. Like John Wayne, he sweeps in to solve our problems. No thank-you needed. Like Jesus Christ, he descended from the heavens to help us discover our humanity. The more jaded the era, the more we have been suckered back to his clunky familiarity. So what if the upshot of his adventures is as predictable as with Sherlock Holmes: the good guy never loses. That is reassuring.

That does not mean he hasn't changed with the times. Superman has evolved more than the fruit fly. In the 1930s he was just the crime fighter we needed to take on Al Capone and the robber barons. In the forties he defended the home front while brave GIs battled overseas. In the Cold War he stood up taller than ever for his adopted country. For each era he zeroed in on the threats that scared us most, using powers that grew or diminished depending on the need. So did his spectacles, hair style, even his job title. Each generation got the Superman it needed and deserved. Each change offered a Rorschach test of the pulse of that time and its dreams. All that has gotten me thinking about how Superman compares to other heroes of our age and earlier ones. I admit to being biased, but here is my take on the World's Mightiest Hero and other claimants to that title:

PHOTO GALLERY