Forced is kind of a strong word. The US was the first to a strong independent standardization system, even though other countries had some individual standards. The US system was effectively the inspiration for ISO in the first place, as Hoover started the US system in the 30s.

The catalyst was that American manufacturing was removed from the conflict, so the US was in the best position to become a world supplier of anything it could manufacture. Especially arms and planes etc. Everyone knew what a pain in the ass sharing arms and vehicles during WWI had been because of the lack of standardized parts, so the allies were already primed to pick a standard either way. The reason the US became the standard is because situationally it became the largest supplier of goods, and also because it had already spent thousands of hours more time on committees to decide why its standards should be what they were. Other countries hadnt done much of that legwork, nor were they risk free areas to produce things in

Bonus cat fact: Hoover had a cat that he named “Mr. Cat”