Would an American attempt to use British First World War debt to stop the G3 and N3 programs have backfired?
Short answerYes; post-1918 Britain remained economically resilient and carried a global security role that the United States was not ready to replace.
NotesBritain's post-1918 economy differed from its physically damaged position after the Second World War. The First World War brought blockade pressure and debt, but it did not leave British cities and infrastructure devastated by bombing. The United States also still relied on Britain to carry much of the global policing burden that Washington did not yet want to assume. Performing that maritime role demonstrated and reinforced British power, just as later global presence would support American primacy. Debt pressure against G3 and N3 therefore risked weakening a security system on which the United States still depended.