Joseph Weiler's Un'Europa Cristiana argues that there should be an explicit reference to the Christian roots of European identity in the Preamble of an eventual European Constitution. Such a claim requires discussing the groundings of European identity, its relation with personal and collective identities, and the relationship between the process of political and economic integration and the national constitutional traditions. This paper finds such a discussion proper and timely, but disagrees with Weiler's conclusions. First, it is held that the positive constitutional law of the Union and its member states does not support an explicit reference to Christian values. It is argued that Weiler's interpretation of "constitutional tolerance" does not correspond to the actual contents of European constitutional law, and that a different understanding of the 'commonality' of the common constitutional traditions is required by positive law. Second, Weiler's argument is found wanting in politico-theoretical terms. A renewed secular or republican principle is found more respectful of the religious freedom of believers and non-belivers, at the same time that an explicit reference to Christian values is found counterproductive in terms of ensuring the civic integration of all residents in the Union.
This paper has later been published in European Law Review 30, 1 (2005), 133-148.