Hi there,
Quite a few options as you can see from the responses so far - indeed, a quick search through the posts in this section will show quite alot of posters here are doing exactly that - sending money back over to the USA to clear and reduce credit card debt.
Ensure that you don't go ahead with walking away from your debt and just leaving it, it's not a good idea at all.
I wouldn't be surprised with the international banking sector in such turmoil, that when things settle a little more that there's more 'communication' internationally between financial intitutions and records about individuals who've say done an international move.
I guess the OP hasn't 'meant' to indeed carry out this plan of walking away, but essentially this is exactly what's caused the 'credit crunch' - people borrowing and then unable to pay back.
Also, if you had to ever return to the USA for whatever reason, you're likely to have you collar felt about the said outstanding debt.
Cheers! DtM! West London & Slough UK!