Anyone offended by public displays of Christmas needs to see a psychiatrist. Are we clear on this? You are a loon if the sight of baby Jesus arouses anger or sadness in you. Get help.

Jon Stewart and his merry band of elves will tell you that the so-called “War on Christmas” is a figment of the imagination, perhaps a result of indigestion after eating too much holiday pudding.

There is something to the argument that there are more important things to worry about than whether people like Christmas. But the assaults against the national holiday are annoying, unnecessary and often disrespectful. I mean, here’s how bad it is in this country: A pastor in Arkansas canceled a play called “Merry Christmas, Charlie Brown” because some nutty atheist objected to public school kids seeing it on church grounds. So Charlie, Snoopy and Linus were thrown under the bus by a Christian cleric. Good grief!

For all of you separation-of-church-and-state fans, here’s the deal: Jesus of Nazareth was a man. In fact, he was the most influential person ever born. A third of the world’s population has signed on to the Christian edicts: love God, and love your neighbor as yourself. That sounds like a good thing.

So, when President Grant honored Jesus by signing into law the national holiday of Christmas in 1870, the nation certified that a positive message of generosity and peace was worthy of a day off. Pretty much everybody was on board.

But not today. In our current state, the Thomas More Law Center has to litigate against attacks on Christmas every year. Anti-religion zealots put up billboards in Times Square denouncing Christmas as a “myth.” Rabid secularists bridle at any mention of Jesus or his nice mom and dad.

To them I say: Peace on Earth and tough. You don’t like the federal holiday? Try to rescind it. See how far you get with that.

And by the way, Merry Christmas to all. Even you loons.

Bill O’Reilly is host of the Fox News show “The O’Reilly Factor.”