I think it has more to do with national security; i.e., not sharing our tech with other nation states that might use it against us. That used to be more of a thing a generation ago. For example, it used to be a crime to export certain computer technology to communist China. Now lot of our stuff is built there.
The reason is nationalism, what I wrote in the parentheses was meant as a tongue in cheek paraphrasing of some isolation supporter, I thought it was obvious because I would never call a person "alien" (as in intruder) seriously. The reason here is "nationalism" because that includes the whole history (which is in turn the reason for it).
