Tara Smith has a very good article reinvigorating and extending the philosophical arguments for religious freedom: “What Good is Religious Freedom? Locke, Rand, and the Non-Religious Case for Respecting It” (Arkansas Law Review 69:4). Along the way she discusses the arguments and counter-arguments of John Locke, Brian Leiter, Jeremy Waldron, Ayn Rand, and others. Direct link to the PDF is here.