Ross Douthat argued the other day that Christmas is actually a difficult season for dedicated Christians:

In a sense, of course, there’s no better time to be a Christian than the first 25 days of December. But this is also the season when American Christians can feel most embattled. Their piety is overshadowed by materialist ticky-tack. Their great feast is compromised by Christmukkwanzaa multiculturalism. And the once-a-year churchgoers crowding the pews beside them are a reminder of how many Americans regard religion as just another form of midwinter entertainment, wedged in between “The Nutcracker” and “Miracle on 34th Street.”
These anxieties can be overdrawn, and they’re frequently turned to cynical purposes. (Think of the annual “war on Christmas” drumbeat, or last week’s complaints from Republican senators about the supposed “sacrilege” of keeping Congress in session through the holiday.) But they also reflect the peculiar and complicated status of Christian faith in American life. Depending on the angle you take, Christianity is either dominant or under siege, ubiquitous or marginal, the strongest religion in the country or a waning and increasingly archaic faith.

Matthew Yglesias sympathizes:

I don’t spend a lot of time agreeing with the Christian right about things, but the whining about the secularization of Christmas is a point I sympathize with. If Christmas were more properly religious, then I think people would have absolutely no trouble recognizing why a secular Jewish person might be not-so-excited about it. Then we could move on with our lives. But the transfiguration of Christmas into a largely secular observance has created a dynamic where lack of enthusiasm for the holiday presents itself as a character flaw—you’re a “grinch” who’s not participating in the “holiday fun” and “Christmas spirit”—in an awkward way. And yet to me no amount of tacky commercialization can really secularize a holiday that has “Christ” right in the name and that’s timed to commemorate the birth of Jesus.

The problem is that religious/cultural conservatives want two things changed about the way our culture observes Christmas.

They want the holiday to be more religious ("Jesus is the reason for the season") and they want it to be observed more universally ("Christmas is our national holiday.") You can't do both.

Well, I mean, you can, if your premise is that this is a Christian country and everybody else is just allowed to live here. But that attitude is at odds with the pluralist character of the United States that, contra various religious right myths, goes back to its founding. So if you want Christmas to be totally pervasive, as many Christians desire, as opposed to merely almost-totally-pervasive, then its religiosity needs to be underplayed. Or if you want to return it to its role as a holiday about Jesus, then it has to be something other than "our national holiday."

Now, obviously, some religious conservatives don't mind if Christmas is secularized but object to people saying "Happy Holidays" in public, while others want the holiday to be more openly Christian but don't expect the entire culture to be subsumed in it. But the general tendency on the right is to demand both things, and there's the rub.