Every single job I've ever had, required me to fill out an I9 form to establish that I am legally allowed to work in the United States.
I am American as fuck. My ancestors were in the Mass Bay and Plymouth colonies. No fewer than five of them fought in the American Revolution, and their descendants fought for the US in every war since then.
If I have to prove my citizenship to get a paycheck... then why in the fuck doesn't some random Guatemalan who doesn't even speak English?