Though that the US had the worse external debt?! Think again! Monaco is the worst with over half a million per person!!! And then comes Ireland and finally the United Kingdom. By the way, French people are also in a worse situation! $46422/person when the U.S. is only at $29610/person...
I got the data from the CIA Fact Book (in Country alphabetical order: Field Listing - Debt - external.) More details on the US deficit can be found on the TreasuryDirect website.
European countries appear in bold. The European Union appears at the end of the list since it isn't considered a country per se.
1 US dollars