Never underestimate the power of negative polarization
Unfortunately this is a weakly held belief, and the elites themselves have embraced protectionism (Biden admin was not a free trader admin) so this is definitely going nowhere.
It definitely is weakly held - but a lot of beliefs in politics are! Not all, there are "core" motivations, but I think a ton of the anti-trade stuff has been culture war piggybacking and does not inherently need to stick to either coalition. It *might*, precisely because it is weak, but I would not at all be surprised if "free trade to lower your car payments" is part of the battlespace in the 2028 primary.
Political elites channeling the inchoate desires of the electorate into an actual policy agenda is what democracies are supposed to do after all, and there are so many "signature" issues of like 2012, even 2020, that have retreated into the background as part of that process. It is a messy world for political coalitions.
How weakly held can you truly call this? Many elites imagine a base of protectionism in the average American, and many people probably somehow hold "I support free trade" and "I support protecting our domestic jobs from foreign competition" at the same time, because they don't know very much. Sure. But these are still huge numbers! If a supermajority of Republicans support free trade, then I can't avoid the conclusion that there's a substantial base of genuine enthusiasm in every group listed.
