Can a person who has divorced himself from Jewish culture still be considered a member of the Jewish national collective? Does Jewish nationalism allow for multiple positions regarding the very connection of Jews with Judaism? This article examines the responses of Ahad Ha-am and Mordecai Kaplan to these questions, juxtaposing their positions with those of three rival exponents of Jewish nationalism: Theodore Herzl, Yosef Hayim Brenner, and the hypothetical case of a Jew who adopted Christianity as his religion. An additional case for comparison is Ahad Ha’am and Mordecai Kaplan’s differing reactions towards the Reform formula of attachment to the Jewish religion, rather than to Jewish nationality.