Tom Diaz

Senior analyst for the Violence Policy Center Tom Diaz says one of the weapons found at the site of the Newtown, Conn. shooting was a variant of a type of gun developed for troops in Vietnam.

In their new book, Lightning Out of Lebanon: Hezbollah Terrorists on American Soil they warn of the presence of Hezbollah militants in the United States. Diaz and Newman say the cells could potentially be more dangerous than al Qaeda.

Senior policy analyst Tom Diaz at the Violence Policy Center, a non-partisan non-profit public policy institute working to reduce gun violence. He's the author of the new book, "Making a Killing: The Business of Guns in America" (The New Press). In the book, Diaz writes how in an attempt to increase profits, the gun industry has introduced more aggressive and lethal guns to the public. DIAZ says they do this free from regulation and under a cloak of secrecy.