The US works with Europe as one big happy family in many other spheres of course.
In this case Europe would perhaps feel that its licence is its licence and does the job it needs to do - document the qualificiations of the pilots it is issued to. Personally I cant see the US having a problem with accepting that - and I guess nobody will never ever know! :-) We have probably spent more words and time on this discussion than it is of interest to the authorities themselves to prioritise or clarify - if they think it needs clarifying from their point of view.
If one day I see in or on the news a US-EU spat over the definition of country with regards to the acceptability or applicability of JAR licences in Europe I'll let you know and buy you a beer. Until then, life is too short. :-)