I think that you will find that American companies who are interested in that concept have actually adopted the DIN rail. It holds things just as well here as it does in Europe.

Square D makes their QO breakers in a DIN-mountable version, known as QOU. There are several companies who make DIN-mounted relays, terminal strips, and other assorted items.

Grab a copy of the DigiKey catalog, and you will see a fair number of DIN-mounted items.