No matter how hard he may try, once an economist makes this argument, the conversation is over, and he will be ignored.
Observe.
Donald J. Boudreaux frequently tells protectionists like Ian Fletcher, “If you think tarriffs improve prosperity, why don’t you erect tarriff walls in your own city and state? Why don’t you save your state worker’s jobs?”
He has never ever been addressed on this.
Mark J. Perry of Michigan University also told Randy Erwin, an autarkist, to Buy Virginian. Alas, when Randy Erwin responded, he did not make a single argument. He just simply said shame on Mark Perry for not saving American jobs.
I am unsure if no protectionist has ever responded to this counterargument, but I understand the reluctance, if not refusal, to respond to it. Protectionism if applied to smaller and smaller areas results in the shrinkage, if not abandonment, of the division of labor. Consequence: poverty. Self-sufficiency does not yield the living standards that free trade does.
I am afraid a hard-line protectionist may pretend the only party hurt by the tarriffs is the “other” side, that’s why it’s un-American to protect anything smaller than the whole federation.
A protectionist would typically discard that argument since “we’re both americans, we help each other”, or “if jobs go to the other city, we can go there to get hired, while we can’t go to China to get hired”.
It’s obviously not a good answer, but enough to convince a lot of unsophisticated people.