You don't necessarily need to be a US citizen. (Not speaking of SpaceX specifically, but commercial space activity in the US in general.) It's possible to get a

You don't necessarily need to be a US citizen. (Not speaking of SpaceX specifically, but commercial space activity in the US in general.) It's possible to get an "export license" which allows you to participate in ITAR-controlled discussions, even if you are a not a citizen or Green Card holder. (My understanding is that it takes some effort, though—it might be hard to find a company that would jump through the hoops without a strong motivation.) Another option is to participate academically through a masters or Ph.D. program—some are well connected with the commercial-space world.