Although it was never an official plank of the Republican Party platform, Donald Trump repeatedly promised during the 2016 presidential election campaign to “bring back” the holiday greeting “Merry Christmas” — which, to hear him tell it had been all but obliterated by the forces of political correctness. As president, Trump repeated the promise yet again in October 2017 at the Value Voters Summit in Washington, D.C., proclaiming, “We’re saying ‘Merry Christmas’ again.”

Without using the phrase “War on Christmas,” Trump was essentially drawing a battle line in a century-old debate that is not just about the 25th of December, but a fundamental disagreement over whether the United States is a secular or a Christian country.