iDAS is really useless in America as well, it is a European flavor of Digital for European iCOM Commercial radio's. Its Europe's P25 equivalent. (Least that is how it was explained to me)
If its iCOM Amateur it's likely DTARS, as NEXTEDGE is a Business Application for Professional 2-way radio and not an adopted voice of Amateur Radio.
DMR is NOT europes answer to P25, and is certainly not 'useless' to america.
P25 was designed for Public Safety in the USA.
TETRA is the Public Safety standard in Europe.
It might have been formed by a European working group, but DMR is the standard for commercial digital radio worldwide.
Two flavours:
FDMA: Kenwood NEXEDGE and Icom are interoperable in conventional mode.
TDMA: The aim is also for interoperability between the other members who have chosen to use the more spectrally efficient TDMA instead, such as Motorola(TRBO), Vertex, Tait and HYT.
No matter where you are in the world, DMR will be sold as the standard for those manufacturers part of the working group.