Same name, mostly same internal components, different chassis (mostly bigger) afaik. Same for Fiesta's except for some models (e.g. ST). I know for the Fiesta since the electronics are the same but the dash components are made for a bigger chassis (to make it fit you have to dremel quite a bit).

The Focus is about the only European-designed Ford which really made it to the US in significant numbers (albeit somewhat late) at all, AIUI.

Even the Fiesta was sold in the US and Canada off and on.