Rich Lowry of National Review Online considers the impact of President Trump’s fixation on a border wall with Mexico.

Trump is paying the price for making The Wall the most powerful symbol of immigration restriction, when it isn’t particularly important or achievable. He piled lurid fantasy on top of absurd overpromising by asserting that Mexico would somehow be made to pay for the barrier.

This worked brilliantly for Trump during the campaign. His rally-goers delighted in his familiar lines about The Wall and engaged in call-and-response with the candidate like the chorus at an old-time revival. The Wall underlined Trump’s tough image and larger-than-life persona. Just as Rome had its Aurelian Walls, America would have its Trumpian Wall — some 1,000 miles long, impenetrable and altogether “big and beautiful.”

Then the bill came due. Or, to be more precise, it didn’t. There was no way, absent the threat of a punitive U.S. invasion, that the government of Mexico was going to suffer the national humiliation of paying for a yanqui border wall. In the leaked transcript of a call with Mexico’s President Enrique Peña Nieto, Trump pleaded with Peña Nieto just to stop saying that Mexico wouldn’t pay for The Wall. And couldn’t even manage that.

So the U.S. government would have to fund The Wall after all (although only as a down payment until Mexico paid its arrears, according to Trump). This was a problem because no one truly believes that a vast border wall — traversing remote territory, causing immense legal complications over the right of way, and costing billions of dollars — makes much sense. Yes, key areas need more robust fencing, but that doesn’t require replicating the Walls of Constantinople.