https://www.eeoc.gov/laws/types/nationalorigin.cfm
"The law prohibits employers from hiring only U.S. citizens or lawful permanent residents unless required to do so by law, regulation or government contract."
Based on that, as long as someone in the US is legally allowed to work, you cannot turn them down because they are a Chinese National.
I'm not saying that Jews shouldn't be regarded as a race. I'm saying that your moral reactions shouldn't be contingent on morally irrelevant descriptive features such as whether the group being discriminated against constitute a race or nation or ethnicity.
It's even possible for people to discriminate against people from a state or city. Should we wait for a special word like "statist" and "citist" to be coined before suddenly discovering that this is wrong?
And don't tell me: "but the reason we want to treat these people differently is because of their moral characteristics, it's not that we are biased against them". Go read Mein Kampt and tell me this isn't exactly the rationale for anti-Semitism stated in it.
My guess would be that .gov will create some sort of regulatory regime around critical infrastructure.
Unfortunately given the trends, being ethnically Chinese will now be another vector for potential job discrimination.
It isn't practical or sensible to discriminate based on nationality. Like, it won't work, and in retrospect it will look as stupid as Japanese internment camps.
Finance and law are decently adept at erecting information barriers. Roping off certain information to non-Chinese nationals would be annoying but with plenty of precedent.
This is the same line of argument as the Muslim ban.
But others actively try to place spies in other countries. It's not wise to treat them as we treat allies, especially given the way they treat their own minorities and political dissidents and neighbors and debtors.