This Thursday, Americans celebrate Thanksgiving, a national holiday that commemorates a meal the Pilgrims shared with their Native American neighbors in the Plymouth colony almost 400 years ago. It is, at least in origin, a religious holiday; the “thanks” are being “given” to God. Yet Thanksgiving does not cause the dissension that official Christmas commemorations sometimes do in America, probably because it is not clearly tied to a particular faith tradition.

Starting with George Washington, American Presidents customarily have issued Thanksgiving Day proclamations, although the secular-minded Thomas Jefferson famously declined. Traditionally, Presidents call on Americans — to quote one of Bill Clinton’s proclamations — “to express heartfelt thanks to God for our many blessings.” Separationist purists object to this sort of thing, which may violate some versions of the Supreme Court’s endorsement test, but the proclamations really do fall within the American tradition of public religious expression.

Last week, President Barack Obama issued his Thanksgiving Proclamation for 2011. In many respects, including its references to God, it’s quite traditional. In one respect, though, it’s not.  In addition to thanking God, President Obama encourages us to “thank each other” for the blessings we enjoy. A subtle redefinition of the holiday? An example of a new secularism in America? I’m not sure; but I do wonder if this idea of appreciating one another will eventually displace the original, religious meaning of the holiday, much as the celebration of family and friends has displaced, for many, the original meaning of Christmas. Not that I object to expressing appreciation to other people. In fact, in the spirit of the President’s proclamation: Thanks, everyone. You know who you are.