The Archbishop of Canterbury backed stricter gun controls in the wake of the Sandy Hook school massacre, saying the ready availability of weapons in a society where fear was already "rampant" pushed people to extreme violence.
Delivering BBC Radio 4's Thought for the Day, Dr Rowan Williams also warned that Britain had "better not be complacent" about the gang-related gun and knife crime affecting its own youngsters.
A minute's silence was held in America yesterday to remember the 20 children and six adult victims of the Connecticut shootings which have thrust the fraught gun control debate back into the political spotlight.
In a defiant response, the National Rifle Association said the answer was arming teachers.
Dr Williams said it was hard to "say and sing the words of this joyful season while we think of lives cut so brutally short and of the unimaginable loss and trauma suffered by parents.
"Nearly 6,000 children and teenagers were killed by firearms in the USA in just two years.
"And we had better not be complacent about the issues of gun and knife crime affecting people in our own cities here.
"In the UK, the question is how we push back against gang culture by giving people the acceptance and respect they deserve so that they don't look for it in destructive places.
"In the United States the question is of course about gun laws - one of the most polarising issues in American politics," he said.
While individuals made the choice to use guns "it makes a difference to people what weapons are at hand for them to use and even more what happens to people in a culture where fear is rampant and the default response to frightening or unsettling situations or personal tensions is violence and the threat of violence," he said.
"People use guns but, in a sense, guns use people too. When we have the technology for violence easily to hand, our choices are skewed and we are more vulnerable to being manipulated into violent action."
He went on: "Perhaps it is true that if all you have is a gun everything looks like a target. But if all you have is the child's openness and willingness to be loved, everything looks like a promise.
"Control of the weapons trade is a start but what will really make a difference is dealing with fear and the pressure to release our anxiety and tension at the expense of others."