Actually the US buyers are the risk, since in US and Australia anyone can issue a chargeback. In most countries you can't unless you have a premium card I think. I read in in Wikipedia some time ago.
I don't think that these sort of scams are generally run using the buyer's personal credit card, and if so this feature of foreign credit cards by no means provides protection against getting scammed by international buyers. Stolen US credit card numbers are a global commodity, so it is very possible for you to be ripped off by, for instance, a Malaysian buyer using a US credit card number.