I understand there could be regulations, but these things not add up for me.

>Applicants must be a United States citizen ... >We hold all information confidential and are an equal opportunity employer.

[1]Title VII of the Civil Rights Act of 1964, as amended, protects applicants and employees from discrimination in hiring, promotion, discharge, pay, fringe benefits, job training, classification, referral, and other aspects of employment, on the basis of race, color, religion, sex (including pregnancy), or national origin.

[1]http://www1.eeoc.gov/employers/upload/eeoc_self_print_poster...