why would china care? if the US wiped its debts then Japan, China and the UK (three biggest owers) would be free on $580, $390 and $320 billion in loans respectively. sounds like a good situation but very doubtful it will happen.
EDIT- scratch that, misread article i was looking at. Looks like they own 60% of the US debt.
Scary stuff...but I'm loving the anarchy of it all because the Politicians and Governments the world over are being hung out to dry, showing just how little power they really have. Everything will have to change!