The grinch says:
As Jews we are forbidden to celebrate Thanksgiving just as we are forbidden to celebrate easter or xmas...This is what happens to those who laugh at our great sages when they issue an eddict [sic] to avoid imitating the secular world on the celebrating of the pagan [sic] holiday of Thanksgiving.
The Sages say:
On the issue of joining with those who think that Thanksgiving is like a holiday to eat a meal: since it is clear that according to their religious law books this day is not mentioned as a religious holiday and that one is not obligated in a meal [according to Gentile religious law] and since this is a day of remembrance to citizens of this country, when they came to reside here either now or earlier, halacha sees no prohibition in celebrating with a meal or with the eating of turkey. One sees similar to this in Kiddushin 66 that Yanai the king made a party after the conquest of kochlet in the desert and they ate vegetables as a remembrance.