First, here's the slide I use in the brief for the U.S.:
So you get the sense of the US coming out of WWII basically 100% in debt and then spending three decades to whittle it down to just over 30%. Then Reagan-Bush jack it up to almost 70%, then Clinton brings it back down to almost half, then W. send its back up to 70% and Obama sends it even higher. On the current course, we're back up in the 100% range within years.
Scary stuff.
Here's a similar chart, but laid out as a map of the European Union:
So what do you take from this: when you get in the range that we're heading for, you run the risk of sovereign default--unless, of course, you're the world's leading reserve currency (used to be 70%, now closer to 60% and dropping).
You look at France at 84% and you realize why Sarkozy is taking on the public unions (Economist cover last week). But you also look at Germany and you have to wonder about it's tough love vis-a-vis a Spain, yes?
Point being, almost nobody in the West is doing well on this score. Lotsa glass houses to go around.