Fraud rates in the US are very, very low. I don't know the stats top of my head for CNP (Card Not Present or Online Fraud) but in general the industry as a whole was running at around 8-12bp couple of years back. It is not something that will materially change interchange rates. International fraud rates tend to vary but not 0bp. Many European countries adopted Chip and Pin early on, which reduced fraud rates but not to the point that will explain a 60+% diff. See my other comment on lobbying in the US.