In light of some recent perplexing commentary, it seemed like an appropriate moment to commend the definitive book about the historical origins of the famous metaphor of the “wall of separation” between church and state, as well as its use in constitutional law beginning at the turn of the 20th century and especially since the famous Everson decision: Philip Hamburger’s Separation of Church and State (HUP 2002).

And just in brief response to the post by Sarah Posner above, it seems to me that both constitutional conservatives and constitutional progressives do not, today, differ on the viability of separation as a principle of religious liberty per se, so much as they differ on the nature and scope of the principle of separationism.   The question, to my mind, is not whether the idea of separationism is “a myth.”  An important variety of separation between ecclesiastical and temporal authority is bedrock — indeed, it was the Catholic Church itself which played a key role in initiating this separation.  The question is instead what the particular contours of the principle should be today — one which thoughtful constitutional conservatives and constitutional progressives can debate without resorting to caricature.  — MOD