BASED ON MY POST OF NOVEMBER 15th.
A couple years back, there was a flurry of excitement over a graph showing that total U.S. debt had reached 350% of GDP. This graph breaks that 350% into its public and private components:
The "public" debt shown here includes debt of federal, state and local governments.
The trend in government debt relative to GDP (the black line) is essentially flat from 1960 until the Paulson Crisis of 2008. And all that time, private debt (the red line) was climbing. So, if the increase in debt relative to GDP is a problem, the fault lies entirely with the private sector.
For notes on sources, refer to this Google Docs spreadsheet.
For the graph shown here, refer to this Excel file.
For data and calculations, refer to either file.