GRAIN OF TRUTH #1: The U.S. didn't really fall too far in the rankings -- it went from 10th place last year to 12th this year. That's partly because Luxembourg got added to the index in the interim and it did better than the United States in the rankings. It's not great, but it's not an exaggerated decline either.
GRAIN OF TRUTH #2: High levels of debt ain't what's holding the United States back in these rankings. Japan has a
much higher debt-to-GDP ratio, but its economic performance ranked eight places higher than the U.S. There are other factors at work here.
GRAIN OF TRUTH #3: If you
burrow into the report itself (.pdf), you find that the primary reason for the drop in the U.S. ranking was a fall in the "Entrepreneurship and Opportunity" score. The primary driver for this? "This fall is driven by a decline in the number of US citizens who believe that hard work will get them ahead and a decrease in ICT exports (p. 10)."
Now this leads to an interesting question: what drives the decline in the belief that hard work will get one ahead in life? Legatum explains that on p. 38:
Low business start-up costs and a positive perception of a country’s entrepreneurial environment contribute to improving citizens’ economic prospects and overall wellbeing. The sub-index also evaluates a country’s ability to commercialise innovation and measures the technological and communication infrastructure that is often essential to successful commercial endeavours. It further provides a snapshot of access to opportunity by tracking inequality and by asking citizens whether they believe their society to be meritocratic. (emphasis added)
And now we get to the nub of it. The decline in America's prosperity score is partly a function of the weak economy -- but it's
primarily a function of citizen perceptions of their ability to get ahead. Government barriers to entrepreneurial activity would certainly depress those perceptions, but so would very high levels of inequality (moderate levels of inequality are a different animal altogether). The more unequal a society is, the less that ordinary citizens feel that their own efforts will yield commensurate rewards. And in the past few years,
the data shows that the United States has become increasingly unequal.