It’s a substantially different issue from the banalization of Christmas trees, in a number of ways, but I think there’s something of the same mentality as emerged from Morgan Hill, CA, here summarized by Glenn Garvin:

… When a federal judge in San Francisco ruled earlier this month that school administrators in a California town had the right to kick out kids for wearing American flag T-shirts because they were offending Mexican-American students, the silence among First Amendment activists and the media was deafening.
…
At Morgan Hill’s Live Oak High School, scores of the many Mexican-American students wore the red, green and white colors of the Mexican flag. But five kids came in American-flag T-shirts. As the five sat at a table outside during a morning break in classes, assistant principal Miguel Rodriguez summoned them into the school office.
The Mexican-American students were angry about the American flags, Rodriguez warned the five, and they had to either turn their T-shirts inside-out or go home for the day. “They said we were starting a fight, we were fuel to the fire,” sophomore Matt Dariano told the Gilroy Dispatch.

As Garvin suggests, this turns the First Amendment on its head — applying the weight of the law to suppress the speech of the targets of threats, and taking the side of bullies who would silence others. The common thread between this mentality and that which renames Christmas trees but not menorahs is a tendency to treat groups of people as if they’ve got some sort of unified racial conscience.
A parent naturally places stronger restrictions on an older sibling’s treatment of a younger sibling than the other way around, because the older sibling ought to know better, because he or she can do more harm, and because we want to inculcate a sense of obligation to protect those who are not as strong. One gets just such an impression from debates handling government’s involvement in cultural disputes — as if to say that Christians need to be adult enough to keep their faith unstated or that white students can live without their patriotic t-shirts so as to get along with their immigrant peers.
But group dynamics aren’t equivalent to the interaction of individuals in this way, and a truly representative and objective government must consider its citizens in their capacity as individuals. Of course, this is a path that diverged along political lines long ago, and so touches on a great number of hot-button issues.