Protecting your own country's production capacity and industry doesn't come without cost. It likely would absolutely be cheaper if we allowed our core industries to fail and be replaced wholesale with American exporters, but that's not what the majority want for the country.
As we're seeing with this trade war as a whole, tightening economic integration with an asymmetric partner puts your sovereignty at risk as well. If we have no industries of our own, and are utterly dependent on a single unreliable superpower, then we lose the freedom to decide on our own future as the rug could be pulled out from under us at any time. The only way to mitigate that risk is to diversify trade and ensure self-sufficiency in our own industries.
As we're seeing with this trade war as a whole, tightening economic integration with an asymmetric partner puts your sovereignty at risk as well. If we have no industries of our own, and are utterly dependent on a single unreliable superpower, then we lose the freedom to decide on our own future as the rug could be pulled out from under us at any time. The only way to mitigate that risk is to diversify trade and ensure self-sufficiency in our own industries.