The gunman in the Virginia Tech massacre, Seung-Hui Cho, should never have been allowed to buy the weapons he used in the 2007 rampage. He had been found mentally ill and ordered into treatment by a court, yet that record never made it into the database of the National Instant Criminal Background Check System used for screening prospective gun purchasers. Prompted by that tragedy, Congress approved a law, signed by President Bush in 2008, authorizing new grant money... (GunPolicy.org)