THE Supreme Court is poised to decide whether the Second Amendment guarantees an individual right to keep and bear arms or only a collective right tied to service in a state militia. While the arguments in the case will draw on history, policy and empirical data, the discussion must at least start with the text of the amendment. snip... How do the two clauses of the amendment interact? Does the first limit the second? Does it give a reason or the reason for the constitutional guarantee of a right to bear arms? At a debate at Columbia Law School in...