Arnaud Mares from Morgan Stanley's London office wrote a report in late August on this exact subject. Unfortunately I can't find it online any more.
If I recall correctly it argued that when you consider the US's Social Security, Medicare, Government Pension Obligations and its guarantee of Fannie & Freddie that total debt is significantly larger than what is ever quoted. Also that debt is often calculated as a percentage of GDP, but that isn't a good reference as GDP isn't necessarily the best indicator of a Governments potential debt servicing cash flow. The USâs ability to raise revenue compared to GDP was lower than most countries. When you combined the two issues, the US goes from a middle of pack debt/GDP ratio to the worst Total Obligations/Ability to raise revenue ratio in the world closely followed by the UK.
If I recall correctly it argued that when you consider the US's Social Security, Medicare, Government Pension Obligations and its guarantee of Fannie & Freddie that total debt is significantly larger than what is ever quoted. Also that debt is often calculated as a percentage of GDP, but that isn't a good reference as GDP isn't necessarily the best indicator of a Governments potential debt servicing cash flow. The USâs ability to raise revenue compared to GDP was lower than most countries. When you combined the two issues, the US goes from a middle of pack debt/GDP ratio to the worst Total Obligations/Ability to raise revenue ratio in the world closely followed by the UK.
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