On Win Ben Stein's Money, a show which I hugely loved a decade ago (during the Jimmy Kimmel era) a question was asked to the contestants (one of which I think was a redheaded Rabbi with a kippa) of "What is the Jewish Thanksgiving?" Even the Rabbi didn't get the answer: "Sukkot". The truth is that most of our holidays are of thanksgiving. Hallel is said on many of these occasions, sacrifices in the temple are designated as Thanksgiving Offerings, Al HaNisim is even said on the minor festivals, we have three Pilgrimage Festivals, any of which could be legitimately designated "Jewish Thanksgiving".
Yet I further pondered this and realized that Thanksgiving, viewed in the sense of American Thanksgiving, does most strongly parallel the Festival of Booths. For one, both are Harvest festivals. Yes, both Pesach and Shavuot are also Harvest festivals as well, but Sukkot is the only Fall Harvest holiday in Judaism, and therefore the produce is comparable. Both holidays celebrate survival in difficult conditions, the Pilgrim survival in harsh New England cold and the Israelite survival in the unbearable steppes of Sinai, and yet both claim divine providence. Both are celebrated by inviting guests to partake in a feast (and even if the Jews don't have physical guests, we invite seven biblical characters and invoke God's name in prayer; likewise traditional Thanksgiving observance includes opening prayers with biblical references). Both are holidays of selflessness. In the Holy Temple, 70 bulls were sacrificed on behalf of the 70 nations of the world. People are increasingly charitable leading up to Thanksgiving, and food drives are the order of the day. Centerpieces and decorations celebrating God's bountiful gifts further increase the beauty of the holiday tables, in the form of cornucopias and lulav/etrog, both also symbols of fertility, as well as hanging fruit usually of the plastic variety for both holidays.
Well, I'm convinced. Moadim L'Simcha and Happy Thanksgiving.