You worked hard to get your U.S. citizenship or your green card. Maybe you’re in the U.S. on a visa granted because of your professional experience or skills. However, some of your colleagues and maybe even your manager don’t seem to see you as anything but a “foreigner.”
“National origin” is a protected class for employees and job applicants under federal law and under Colorado state law. Even if a person wasn’t born in another country, they can’t be discriminated against or harassed because they’re perceived as not being American or even because their spouse was born in another country.