What does "Made in the USA" really mean?

Stages Power Meter for Shimano Ultegra cranks
(Source: https://www.mec.ca/en/product/5047-314/Power-Meter---Shimano-Ultegra-6800-%28Gen-2%29) 

Stages Power Meter for Shimano Ultegra cranks (Detail)
(Source: https://www.mec.ca/en/product/5047-314/Power-Meter---Shimano-Ultegra-6800-%28Gen-2%29) 

So, where was this product made? The Shimano bicycle crank arm is designed and made in Japan and the power meter, attached to the side of the crank arm, is "Assembled in USA". The electronics inside are most likely made in China.

Like Apple, Stages probably does its research and development in the USA, and outsources the circuit board assembly to an Asian contract manufacturer using components from multiple countries.

The sort of multi-national supply chain is increasingly common. But in this era of uncertainty about the future of trade agreements how are products like this classified? There are content rules, but some American trade fundamentalists expect everything to be made in the USA. A pipe dream? Most likely, but that won't stop people from pushing for more domestic manufacturing.

For manufacturing to increase in the USA the obvious options are that either American workers will have to accept lower, Chinese-level, wages or American consumers will have to accept higher prices. And neither of those were planks in Donald Trump's "Make America Great Again" platform.