CBS host Bob Schieffer on Sunday reflected on the recent massacre of 20 elementary school children in Connecticut and wondered "to what depths of horror must we sink" before lawmakers and politicians begin to take the issue of gun violence seriously.

"By now, the pros and cons of the gun issue are well known," Schieffer said in his Face the Nation commentary. "But here is the question that must be asked: Is what happened Friday the new normal? Of course, there are legitimate reasons for both pleasure and protection to own guns, but if the slaughter of innocent children is not bad enough to make us re-think what we can do to keep guns out of the hands of the mentally ill, what is bad enough?"

"To what depths of horror must we sink before we say this cannot be tolerated? Are we willing to settle for a culture in which kindergarten children are no longer safe in the classroom and a visit to the mall or a movie is a life-threatening experience?"

"In recent years there has been no effort to address this problem, no piece of gun legislation was seriously considered during this session of Congress," he continued. "It is a subject no one wants to talk about for fear of offending the powerful gun lobby. It is time to remember what Ed Murrow told us, that we are not descended from fearful people. Our forefathers had the courage to tell the most powerful country of their day, 'You have gone too far, we can tolerate this no more.' And upon their courage, America was built. Have we, their descendants, become so afraid of the possible political consequences that we are unwilling to explore ways to make safer world for our children? I cannot believe we have. I think we are better than that."

During a panel segment later in the show, Schieffer asked Lehigh University professor Dr. James Peterson if the country had reached a "tipping point" to reverse the trend of gun laws becoming more lax in recent years.

"There's a way in which we're moving in two different directions at the same time," Peterson explained. "Proliferation of guns and the frequency of these kinds of mass shooting incidences, and then the other direction, our policy seems to be one that wants to be more freedom and more for a free-market system in terms of guns and gun ownership."

"You think about the whole terroristic element of this," he added. "This should be a new front on the war on terror. And it needs to be domestic, and it needs to be directed around some of these issues of the proliferation of guns."

Schieffer agreed: "That's the part that I find kind of interesting about this. After 9/11, we turned this culture upside down, we doubled defense budget. If this person had had -- I'm sorry to say this -- but if he had had an Arab name, people would be going nuts about what we ought to do right now. And yet, we can't seem to decide, is this a problem we can solve?"

Watch this video from CBS' Face the Nation, broadcast Dec. 16, 2012.