There is no war on Christmas or Christianity for that matter. People are free to believe what they want and to practice how they want. They are free to join churches and teach their children their beliefs in their homes. They are free to set up Christmas displays on their property and on their church property. No one is stopping them. What there is a war on is the entitlement that Christianity has enjoyed over the years. Public buildings, public lands, public meetings and public schools should have no religious symbolism displayed or prayers said. Public includes everybody.
No one gets preferential treatment. This is a nation of many different people with many different beliefs and all of those beliefs need to be respected equally.