The US does not exempt the UN earnings of its taxpayers from taxes. The purpose
of the reimbursement system is to place UN staff members subject to taxation in
the position they would have been if their official emoluments were not taxed.
Hence, it is intended neither to provide a benefit, nor to place the staff
member at a disadvantage, in relation to other United Nations staff members who
are not required to pay taxes to a Member State on their United Nations
emoluments (latest tax circular).