Require a mental illness check before being able to buy a gun.

The tragedy in Newtown has revived a national debate about gun control, focusing attention on the laws (and loopholes) governing gun ownership in America, and raising a host of questions about how to prevent future Newtowns (and Auroras and Columbines and Virginia Techs). Chief among them is how to keep weapons out of the hands of mentally ill people. Newtown shooter Adam Lanza, whose mother was reportedly seeking to have her son committed to a mental institution, carried out the shootings with weapons that had been legally purchased by his mom, but across the country it's frighteningly easy for people with serious psychiatric problems to purchase weapons.