Liberty ships adapted British precedent to American mass production

Would the United States have created a mass-produced merchant ship without Britain's Liberty-ship design?

Probably yes: Britain supplied inspiration and requirements, but the standardized mass-production program was fundamentally American.

British requirements and existing emergency cargo designs supplied important precedent, including ships produced in Canadian yards. The United States selected a design it could simplify, standardize, and manufacture reliably in enormous numbers. Calling the result merely a British design misses the American industrial system that made the Liberty ship historically decisive.