This is a tempting explanation, but other developed countries still have powerful labour movements and the ability to take collective action, despite a similar level of dependence on Chinese imports. I'm thinking particularly of France with both the gilets jaunes movenent and its frequent strikes, though it's true that those are more common in service industries and the public sector than in manufacturing.

For better or worse, Americans have long identified more with businessmen and less with the working poor than their counterparts in the rest of the West. At least back to the 1920s and the quip about "temporarily embarrassed millionaires".