The thing is, Christmas, like the Ten Commandments, is an invention. I'm not talking about the concepts behind these things. The Nativity is real, but we haven't the foggiest idea when it occurred. (The shepherds were up in the hills with their flocks, so winter doesn't make a lot of sense.) The Star of Bethlehem would have been visible for a while, if not over a wide area. However, the Nativity is most emphatically not Christmas, and no one has said so. In fact, Christmas is the Christ Mass -- the church service dedicated to the birth of Jesus. Given that no one by the third century knew when Jesus was born, exactly, Roman Christians set the feast of Jesus at the same time as the Saturnalia. That allowed syncretism that could keep Christians from the executioner, on the one hand, and damnation for idolatry, on the other. Christmas is a church service, not a date, not the nativity. I hope I'm not the first person to point out to you that, when the Protestant Reformation occurred, many of the more radical protestants rejected Christmas. The first two generations of protestants were Bible scholars, knew that the nativity's date was uncertain, and wanted nothing to do with the idea that Jesus would be celebrated for a birth date coinciding with pagan rituals. The Puritans made Christmas celebrations illegal in England. (A good article on the ban is here.)
Charles Dickens recreated Christmas with that book of a man forging chains in life and blessing a crippled boy. That was a bold bit of public relations. After that, America began making a visual Christmas, a Christmas of a particular sort. Just as with Thanksgiving's Puritan holiday getting foisted on the rest of the nation (founded earlier by different folks), a particularly northeastern form of Christmas...with snow and sleds and candy canes -- all products of New England -- became the universal and unequivocal Christmas. German immigrants bring their fader Christmas and Santa with Black Peter (who gets dropped as not fit for marketing). That gets sold on television and in film, so all of us wish for a "White Christmas," even in Arizona.
Christmas, in the form of a sled full of presents, is purely a merchandizing invention, a marketing construct. I am not saying that it is corporate America tricking us into celebrating Talk Like A Pirate Day. No. It's just that this Christmas is an accidental agglutination of commercially successful details -- each having been chosen by the marketplace, each being top seller. When a southern city defiantly puts up a sled, fake snow, elves, and the like, it is defying secular liberals on behalf of a commercial image, not the Christ Mass, and not the Nativity. They claim to be defending "Christmas," but that Christmas is not the christological moment of the Incarnation of God as man.
Surely, surely, surely everyone knows that the "washing machine sized" monument of the decalogue that Judge Roy Moore was fighting for was not chiselled by Moses or the finger of God. In fact, it came from Hollywood. No joke. The "Ten Commandments" came from the marketing of The Ten Commandments via the Fraternal Order of Eagles. The FOE put these things up around the country, and one of them fell into the clutches of a fundamentalist judge. From there, all wrath broke out. Those who mobilized for the display of the Ten Commandments were, in fact, rallying around a marketing freebie.
What's interesting about these two causes is that they are both fights about wrappers rather than contents. The box, rather than the gift, is what is important. It isn't the celebration of the incarnation of Christ that we're fighting over, but whether or not someone says "Merry Christmas" (and how often does "merry" come up in other phrases in contemporary American?) or "Happy holidays." In other words, they are about outward display of washing machine blocks of granite and greetings, not about Christianity and adherence to the rules of Mosaic law.
I'm tempted to agree with Umberto Eco, whose Travels in Hyper Reality suggested that Americans like the recreation more than they do the real thing, that the replica of Graceland is better than Graceland because it has been edited and had its reality heightened and tweaked. However, there is a more philosophical and religious crisis at stake here. Our preference for simulacra might pump money into the Hard Rock Cafe, but it won't get us screaming at one another on the nightly news.
Instead, I think that the Protestant Reformation, the thing that made us most at war with Christmas, has made us most desperate for "Merry Christmas" and mangers and Christmas Pride. Protestantism's emphasis on the individual's role in interpreting scripture and choosing one's denomination, and the congregational churches' emphasis on lack of authority in structure, has led Christians into greater isolation from one another and no visible mark of their faith. Jesus said that we need no external marks, that we should concentrate on the cleanliness of the soul, not the washing of the hands. However, that leaves people nervous for some reason.
The ichthus display on car trunks is a sign (the "fish symbol"). It says, "I am a Christian." Why? It is the same reason as the Christmas Pride and the decalogue-as-rock: it is a way of shouting out one's Christianity, of screaming one's identity, or one aspect of one's identity, at the top of one's lungs. I do not know why, but it's clear that the people involved feel like their identities are threatened, feel like they are sliding into oblivion and irrelevance, and they are striking back with poor aim and no introspection.
My feeling is that people telling the world so loudly that they are Christian do not mean that they are Christian. After all, the people they are shouting at are Christians as well. The people they are shouting at are not enemies or ashamed of the incarnation of Christ, either. Instead, they are following the dancing shells of ideology and guessing that the pea (the self) is under this particular walnut half. I'm afraid that they're wrong, but I'm also afraid that we cannot convince them of that. Instead, we can try to reassure them and hope to help them discover what it is that is truly making them afraid.