A new shot will be fired in the development of constitutional law this term when the U.S. Supreme Court decides the meaning of the Second Amendment in District of Columbia v. Heller. Although the Court has only touched upon the Second Amendment in a few dozen cases, only once has the Court even begun to address its  meaning. But the question presented in Heller requires a clear statement about its meaning. The Court will have to choose between three competing interpretations of the Second Amendment, a task made more difficult by a profoundly disappointing brief filed by the Justice Department in the case. What it does, and does not, decide will likely forever shape the future of Second Amendment jurisprudence and gun rights in America....