ONLY SUPERHEROES have superpowers. But are superpowers the only ones who have superheroes? Let me explain: In the six and a half decades since the birth of the superhero comic-book genre, a disproportionate number of super-powered men and women have–surprise, surprise–turned out to be American citizens.

Most were born in the United States. Others, such as Superman, were aliens (illegal, presumably, given the immigration restrictions in place when he arrived in 1938) who decided to make America their home. And thank God for that. Had that tiny spaceship from the planet Krypton landed in Munich or Moscow during the perilous summer of 1938, comic-book history might have turned out very different.