Just how bad is the US national debt?
The Economist recently added a page called the Global Debt Comparison. I spent a bit of time playing there, and then downloaded the data.
Here is a chart of public debt by country, based on estimates for 2010, for the 20 largest economies. The horizontal axis is debt per capita, the vertical axis is debt as a percentage of GDP. Can you spot the United States?

In trying to pick the US from this lineup, my guess is you went to the top right. That outlier is Japan, whose debt is almost twice their annual GDP. The next one down is Italy (121% of GDP). At the far left you have India, whose public debt as a percentage of GDP is higher than the US, but because their per capita GDP is so much lower than the US, the per capita debt is also quite low.
The US is the one in red, 60% of GDP and $28,693 per person.
Not to say that deficits don’t matter, but it does put it into a bit of perspective.
(H/T Freakonomics)