I've often flown short flights around the US on aircraft built by non-American companies whose range is less than is required to make a traditional Atlantic crossing. The Airbus A319-100, for instance, has a range of 2,400 miles while the distance from London to NYC is 3,440 miles.
How do manufacturers get their small planes across oceans? Do they operate factories in on all continents? Do they fly via Iceland or Greenland?