The U.S. Postal Service wants to exempt its competitive products like Priority Mail and package services from the universal service obligation. Doing so would allow it to cut back on offerings in sparsely populated areas where business is thin.
The Postal Service argues that those services shouldn't be treated differently than those of competitors such as FedEx, DHL and UPS. An exemption would allow the Postal Service to choose which competitive products it offers in a given market, and what standards of service to apply. Products covered by the universal service obligation such as first-class mail must be offered in a uniform fashion across the country.
But even if the agency gets approval from Congress to exempt those competitive services from universal service, an international treaty would create a paradox: The Postal Service would still be required to deliver mail and packages coming into the United States from overseas, even if it doesn't offer the products in a given market.
Courtesy of postcom.org