The fine lawyer bloggers at
Law And The Multiverse have said that one of their most common questions is "What's Superman's immigration status?"
They answer that question
here . Here's a little bit of their cogent and well-reasoned post:
...The actual history of Superman comics is of note here, as Action Comics #1 was published in 1938, when the country, still reeling from the lingering effects of the Great Depression, was smacked by the Recession of 1937. Unemployment was well north of 15%. The Dust Bowl was recent history. So the idea that a motorist in Kansas would discover an abandoned baby on the side of the road was depressingly plausible. In an age when immigration laws were far more lax than they are today, no one was going to ask any questions about the origin of such a child or his lack of a birth certificate....
Adopting a random infant is actually a lot harder to do these days, as state laws about that sort of thing create a lot of hoops for potential parents to jump through. The upshot is that some kind of documentation would be needed for an infant who basically appears out of thin air. That would require clever forgeries at the very least.
Or a retcon. In at least one version of Superman’s origin story, Jor-El did not place him in the rocket as an infant, but Kal-El was actually in a “birthing matrix” and was thus “born” on Earth, making him a natural born citizen of the United States and thus eligible to be President. Or at least that’s what the Supreme Court held in a 9-0 ruling. Depending on your views of Supreme Court jurisprudence, this may not even be the most fanciful thing they’ve ever done.
I tee-hee'd over that last sentence.