Mark Oppenheimer concentrates on the difference between a religion and a nation-state:
[D]o not confuse Zionism with Judaism. Raise your children to see them as analytically separate. That does not mean raise them to be against Israel, anti-Zionist, whatever you want to call it. If Zionism is deeply important and true to you, give it to your children. But while contemporary, post-1948 Zionism may be as important as Judaism (or not), and may be theologically interwoven with Judaism (or not), it is not necessary to Judaism.
Because, to begin, nation-states are all imperfect, flawed, and often brutal, while a true religion should not be. (That previous sentence may be too hard on nation-states and too easy on religion, but I hope you will take the point: countries are of this world, while religion can be an aspiration to something better.) And, what's more, the worship of a nation-state is idolatrous. It is bad Judaism to make Judaism and Zionism—in terms of support for a particular contemporary nation-state—coequal in one's loyalties.
The Dish 