If said alien were deemed a person then it would have US citizenship (unless it’s “parents” where diplomats or occupying soldiers). The real question is; must a natural person be a human being>
My understanding is that it’s no longer generally recognized for private property ownership, but that most nations do (theoretically, at least) claim all of the space in the funny-shaped wedge projected from the center of the Earth through the borders of the nation. If Krypton were in the US’s particular funny-shaped wedge at the moment of Kal-El’s birth, then arguably, by virtue of being in that wedge, he was born in American territory.
In the particular story (Superman becomes President) referred to, his identity had already been revealed. He had been shot by robot mini-supermen with laser eyes that burned his Clark Kent suit and revealed his Superman costume underneath. This happened on live TV, so everyone knows.
Clark Kent was legally adopted by the Kents; they told the authorities he was a foundling (which he was), brought him to an orphanage, then showed up a few days later to adopt. I would assume that the orphanage would have gotten him a birth certificate saying he was born in Smallville to unknown parents.
So Clark shouldn’t have any issues: he’s a US citizen.
Superman, OTOH, is a different issue: he might not be regarded as a citizen, since no one knows he’s really Kent.
There have been a number of stories recently involving various governments taking issue with “American” superheroes operating on their soil. In most cases, the argument is valid. A couple Green Lanterns recently pointed out that, although they were Americans, when they wear their rings and uniforms they are responsible for the entire planet - borders be damned. The Chinese superhumans attempting to stop them didn’t agree.
If the lawyers successfully argue that a “person” need not be a Human (using the generally accepted definition of Human = the Terran species known as Homo sapiens), then ISTM that a xeno-Terrestrial born on US soil would qualify as a native-born American. (Subject to the rules of the parental xeno society on dual citizenship.)
I am not an immigration lawyer, this point has not been raised (AFAIK) in American courts, feel free to give it a try but don’t hold me responsible.
Wowza, I was adopted like that. (Dropped off at an orphanage for a couple of days so they could legally adopt me). Cool.
Stay away from Kryptonite, just in case.
Only an idiot would vote for Superman as President, because there’s always a disaster somewhere in the world. When some guys get trapped a mile underground in a coal mine in Australia, he has to fly off to rescue them, right? And when a ferry capsizes in Indonesia and there are 800 people floating in the shark-infested waters, he has to fly off to save them, right? When will he have time to be President?
Would you vote for him knowing that he would constantly have to fly around the world saving people? And what if he didn’t? Would you vote for the kind of person who would let all those people in that skyscraper in Moscow burn to death because he had to finish reading that NSA report on terrorist activities?
Well, yes, I’d certainly vote for him. (In theory, since I’m English, and don’t get to vote in Presidential elections)
Of course, he could read that NSA report in about 1/2 a second, leaving him plenty of time to rescue those Ruskies.
I could be Superman’s younger sister! 
This OP is better suited to Cafe Society.
samclem
Are you going to deport him? Go ahead.
I don’t know which issue this can be found in, but according to the Supermanica wiki,
“Although Superman apparently lacks jurisdiction to apprehend criminals outside Earth’s solar system, he has been awarded honorary citizenship “in all the countries of the United Nations”, along with a special “golden certificate” empowering him to apprehend criminals in U.N. member nations and to travel in and out of those nations without a passport.”
Now, whether this gives him permission to permanently settle in any one country is unclear. This does allow him to come and go in any U.N. member nation as necessary to apprehend criminals or to rescue people. And it probably doesn’t apply to his Clark Kent identity. Presumably Clark Kent is a citizen of the U.S. and needs passports to enter foreign countries under his job as a journalist in order to protect his secret identity. But as long as he enters foreign soil in his Superman identity and remains in the costume, he is free of all bureaucratic restrictions, at least as far as U.N. member nations are concerned.
There is a superman = F
There is an illegal alien = T
Superman AND illegal alien = F
Pre-Crisis, Superman had been granted global citizenship by the U.N.
Yes - as quoted in the post just three posts above yours, with chapter and verse.
I believe you’re mixing up two stories, there. The action-figure bit is from “Whatever Happened To The Man Of Tomorrow?”, which most assuredly does not involve him running for, or getting elected to, any office. He receives a rather nice trophy, but that’s about it.
The possible future in Armageddon: 2001 involved him signing on with the Presidential campaign of his old pal Pete Ross, who’d figured that an award-winning writer with media connections would be a useful guy to have around – never realizing just how useful, as when Clark threw himself in front of the rest of the bullets coming at him. The first shot put Pete in the hospital, and out of the race – but the next five only tore Clark’s shirt, exposing the ‘S’. Which, of course, made him a lock for the White House right when Pete asked him to carry on in his stead.
That’s when the Supreme Court was called in to determine his eligibility, and unanimously ruled that the birthing matrix was like unto the artificial womb of a test tube baby, such that he was born on American soil.
Oh, and:
That’s pre-1986. Then there was this big time-travel thing where history started back over from zero, and everything unfolded differently; among many other changes, the Kents didn’t go through the two-step at the orphanage. Clark himself grew up thinking he was (a) human, and (b) their kid; he cheerfully became a high-school football star – and even after they told him what they knew and showed him the rocket, he concluded he was probably some weird Soviet super-soldier experiment to put a fetus up in orbit and expose the drugs in its system to radiation or something.
Where/when did this happen?
Unusual, or so it seems in terms of the Paperwork Hell that adoption is usually described as.