Maybe Mexico should demand a refund.

In the meantime, and with much less fanfare, construction continues on a wall of much further-reaching consequences. You see, while the wall on the border is supposed to repel immigrants and smugglers, this one repels something many of us find even more threatening: contradictory opinions. Consider three recent news stories:

• In Washington, the White House announces it will cancel government subscriptions to The Washington Post and New York Times. The administration calls it a cost-saving measure, but the truth is obvious. Trump famously hates both newspapers.
• In Citrus County, Fla., county commissioners reject the local library’s request for a digital subscription to The Times. Says Commissioner Scott Carnahan, “Fake news, OK, I agree with President Trump. I don’t want the New York Times in this county.”
• In Coeur d’Alene, Idaho, the library reports that an unknown patron has been hiding books critical of Trump and conservatism, deliberately mis-shelving them in other sections of the library. As that person explained in a note, “I am going to continue hiding these books in the most obscure places I can find to keep this propaganda out of the hands of young minds.”

The sheer snowflakery of all this cannot, of course, be overstated. And yes, it reeks of anti-intellectualism, that proud, bullyboy ignorance that has too often fed books — and bodies — into bonfires.

But this also speaks to barriers of intellectual — and emotional — separation that now zigzag across America like a scar, splitting towns, colleges, churches, workplaces, friendships and families. Nor is the barrier only being built from one side. As liberal college students demand “safe spaces” and “trigger warnings” so they won’t have to confront contradiction of their beliefs, it becomes painfully clear this wall is a bipartisan project. And that should concern us all.

This is no argument for false equivalence, nor even for civility. But it is an argument for intellectual freedom — for honoring people’s sacred right to speak and to hear.

The genius of America has always been that it believed in the marketplace of ideas, believed we should have access to the broadest possible range, and that if we did, we would, more often than not, choose the good over the bad, the right over the wrong, the intelligent over the stupid.

Yes, that trust has been sorely tested lately, but is the answer to abandon it completely? To do so would be to abandon everything that makes this country worth the trouble. To do so would be craven and un-American. As in commissioners of a podunk Florida county defending its citizens from The New York Times.

One doesn’t know whether to laugh or cry. That wall Trump is trying to build against immigrants will go down as an expensive boondoggle. But you know what will cost us more in the long run?

Any wall we build against ourselves.