Interspace are named for where they operate, like OS&C, not by 'American'. Stations advertise this best;
Waterloo - New London
Newark - New York
Roppongi - New Tokyo
Bonn - New Berlin
Furyoku - Okinawa
All 5 names (4 vanilla, one Disco-added) are associated with a place in the area they are in. Roppongi, for example, is a district in Tokyo, or at least the prefecture. (Hard to remember which off the top of my head.)