You may want to review the USPS
international mail manual. Best I can figure, plain old Express Mail International provides tracking, but not delivery confirmation. The regulations are not entirely clear, unfortunately.
I take the conservative view (especially for high value content) that tracking is
not the same as delivery confirmation. For true delivery confirmation with Express Mail International, you need a return receipt . Fortunately, return receipt is included in the EMI the price. It's my experience that you must specifically request return receipt as an added service. Unfortunately, only a
small number of countries provide return receipts to the sender via USPS.