Chanuka Bush
Question
It may interest you to know that Rav Moshe Feinstein and Rav JB Solivetchik are both on record saying that its 100 percent permissible for a devout Jew to mark thanksgiving with a festive dinner. Rav Moshe has two teshuvot on the subject. In the first we says that though we should not make weddings on Christmas due to maras ayin, that prohibition does not extend to Thanksgiving, because Thanksgiving has no religious significance. In the second he rules conclusivly that there is no inyan of chukot hagoyim here. His only caveat is that you should not create a sense of obligation, and suggests therefore that it would be wise to occasionally miss a year. As for Rav Solivetchik, it's well known that he would hold shiur early (though he wouldn't cancel it) on Thanksgiving Day so that he would have time to get home to Boston for dinner.
Answer
Answered by Aaron AbadiI have a Teshuva from Rav Moshe to the contrary. He says "it is certainly Assur (not permitted). Sorry! Anyone who wants a copy should email me. AA