In this essay, I analyze the efforts of a French Roman Catholic organization committed to reproducing the ubiquity of Roman Catholic built space in the landscapes of Paris and its suburbs. Over its nearly 100-year-existence, the "Cardinal's Construction Site" has variously advertised its efforts as those necessary to combat communism, modernism, and secular apathy. I argue that its labors demonstrate how two concepts central to the anthropological study of Roman Catholicism exist in powerful tension. While Roman Catholicism has the capacity to recede into the background-in part through the ubiquity of its built space-and appear as nothing more than the unmarked or normative culture in countries in which it is the majority religion, its power as a social "institution" is maintained by numerous practices that invoke the "passions." That is, in order to uphold the status that allows it to go unmarked, Roman Catholicism must also function as what Valentina Napolitano has described as a "passionate machine." It is in part Catholicism's capacity to uphold the normative by way of the passions that explains its current role in the xenophobic politics of Europe in the present. In this essay, I analyze the efforts of a French Roman Catholic organization committed to reproducing the ubiquity of Roman Catholic built space in the landscapes of Paris and its suburbs. Over its nearly 100-year-existence, the "Cardinal's Construction Site" has variously advertised its efforts as those necessary to combat communism, modernism, and secular apathy. I argue that its labors demonstrate how two concepts central to the anthropological study of Roman Catholicism exist in powerful tension. While Roman Catholicism has the capacity to recede into the background-in part through the ubiquity of its built space-and appear as nothing more than the unmarked or normative culture in countries in which it is the majority religion, its power as a social "institution" is maintained by numerous practices that invoke the "passions." That is, in order to uphold the status that allows it to go unmarked, Roman Catholicism must also function as what Valentina Napolitano has described as a "passionate machine." It is in part Catholicism's capacity to uphold the normative by way of the passions that explains its current role in the xenophobic politics of Europe in the present.