American Jews should celebrate the existence of Christmas. We should feel joy when Christmas comes around, and not just because American Christianity is tolerant. American Jews should feel joy specifically because America is a Christian country -- the dominance of tolerant Christianity means that more non-Jews are fulfilling God's plan for them.
Unlike other religions, Judaism does not seek converts. In fact, Jews are required to discourage non-Jews from converting. Also, unlike other religions, Judaism does not bar the gates of heaven to non-members. Jewish thought says that God does not care only about the Jews -- the billions of non-Jews worldwide have obligations to fulfill as well. While Jews are obligated to fulfill 613 commandments (mitzvot), Judaism says that non-Jews earn a place in the world to come (olam haba) by adhering to seven simple rules, known as the Noahide Laws.
Six of the Noahide Laws were given by God to Adam and Eve in the Garden of Eden. The seventh was given to Noah after the flood. Because the entire set of laws was not completed until Noah's time, Judaism refers to the laws as the Noahide Laws.
The first three Noahide Laws concern interactions between humans. God designed a world where human interaction plays a primary role. If human interaction must consume most of our time, and the goal of life is to become closer to God, then God clearly means for us to elevate our interactions and, by doing so, draw near to him.
The first of the Noahide Laws prohibits sexual immorality. The source for this Law can be found in Genesis 2:24: "Therefore a man shall leave his father and his mother and cling to his wife and they shall become one flesh." Several prohibitions are derived from this biblical statement. Homosexuality is forbidden, both for males and for females, since the goal of human relationship is a man-woman relationship for the purpose of having children. Even if a male-female couple cannot have children, their relationship still carries with it the godly seal. As Rabbi Yirmeyahu Bindman, author of an authoritative book on the subject, writes, "(homosexual relationships) remain empty of all the transcendence that correctly addressed love receives from above."
This lack of transcendence applies to other relationships as well. Adultery is banned by the Noahide Laws, as are incest and bestiality. Premarital sex is frowned upon, since it cheapens the act of sexual intimacy.
Because male-female relationships have the ability to transcend the physical, the Noahide Laws frown upon celibacy. God created the sex drive for a reason. The rabbis teach: "Do not talk to God and think of a woman; talk to a woman and think of God."