Immigration is defined in law in a pretty straightforward manner. If you cross US borders, you are defined as an immigrant unless you fit into one of twenty two different non-immigrant categories defined in 8USC§1101(a)(15). Each letter subsection of that section corresponds to the more familiar letter codes for non-immigrant visas. Most people are not familiar with all of them but the definitions aren’t particularly complex or confusing. If you’re seeking to cross the border as an immigrant, there are several sections under 8USC Subchapter II that apply. If you are a citizen, you’ve got to have a passport to leave or return.
Neither side in the immigration debate seems to want to lay out, specifically, what sections of the law they wish to change and how exactly they want to change it. Are there extremist imams getting R visas and endangering the safety of americans (mostly muslims)? That’s not the way we talk about immigration. Why,exactly, is the secretary of Labor involved in the issuance of visas?
We’d be a lot better off if discussion of the law had a lot more law in it.