And, it does so happen that every major aviation triumph was american
Aircraft pressurisation, American? Nope.
Packard-Le Père LUSAC-11, (1920, a modified French design, not actually pressurized but with an enclosed, oxygen enriched cockpit)
Engineering Division USD-9A, a modified Airco DH.9A (1921 - the first aircraft to fly with the addition of a pressurized cockpit module)
Junkers Ju 49 (1931 - a German experimental aircraft purpose-built to test the concept of cabin pressurization)
Farman F.1000 (1932 - a French record breaking pressurised cockpit, experimental aircraft)
Chizhevski BOK-1 (1936 - a Russian experimental aircraft)
Lockheed XC-35 (1937 - an American pressurized aircraft. Rather than a pressure capsule enclosing the cockpit, the monocoque fuselage skin was the pressure vessel.)