During America's industrialization era, in the late 1800s to early 1900s, some of America's brightest weapons designers: Benjamin B. Hotchkiss, Hiram Maxim, and John Browning have all moved to Europe. Hotchkiss and Maxim setup their businesses in Europe, while Browning went to work for FN in his later life. It is quite ironic that the US Military had to import the Maxim Gun and its technology from Britain, when it was a technology invented by an American-born person. So, things are not as clear cut as you are describing it to be.