credit card debt, tick tock, tick tock

Mish is normally quite accurate, but this piece in the post does not make sense to me:

The UK is behind in the housing cycle, as far as I can see. However, it is easier in the UK for consumers to default on consumer debt, whereas in the US it is easier to default on mortgage debt. May explain the difference? … e-friends/

ABCP implies that there are assets backing the commercial paper. What assets back up credit card debt? Surely this is unsecured debt? So the return in event of default (following chapter 13 bankruptcy in the US) is nil.