An article in Wikapedia includes three lists of countries of the world sorted by their gross domestic product (GDP) at purchasing power parity (PPP) per capita, the value of all final goods and services produced within a nation in a given year divided by the average (or mid-year) population for the same year.
The United States is near the top in all three tables. All of the countries ahead of the US are either city states like Lichtenstein and Luxembourg, or oil rich countries.
So the rumors of our demise are greatly exaggerated. We do have to get our Federal budget closer to balanced, however.
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