How can America put an end to the school shootings that are taking place with such tragic regularity? In the weeks following the Sandy Hook shooting in December - which left 20 children and seven adults dead, along with their murderer - the country has been searching in earnest for answers.
What if, some have asked, teachers at the Connecticut elementary school had themselves been armed? Might the massacre have been averted?
The governor of Virginia, Bob McDonnell, thinks so. "If a person like (Sandy Hook's principal) was armed and trained, could they have stopped the carnage? Perhaps," was his conclusion in the week following the attack.
His comments drew a furious response, not least from the head of the American Federation of Teachers. But plenty of Americans agree with him and, across the country, legislators are taking steps to change their state laws to allow firearms in the classroom.
David Burns, a Republican in Maine's state senate, is one of them. He is pushing a bill that would allow teachers in Maine's public schools to carry concealed weapons to class.
"The role of an educator has changed since we've had so many attacks on our public schools and our children," Mr Burns, a former law enforcement officer, says. "Educators have evolved in many ways, and they do a lot of things out of necessity. This would be one more thing that we would ask willing participants to do in addition to their regular work within the school system."
Under his proposal, any teacher or other school employee who passed a psychological test, undertook a week's training and obtained a state permit could carry a firearm. Like air marshals, their identities would be concealed from all but the school's governors.
Mr Burns rejects the suggestion that safety would be better served by further clamping down on weapons in schools, rather than encouraging them. "That would be great to keep guns out of schools altogether and not have things happen like happened in Connecticut but that's not the world we live in... Parts of our state are extremely rural. I have places in my senate district where the response time by a police agency can be over an hour."
And it is better to have one or two discreetly armed teachers than conspicuous security guards, he argues.
According to the Law Center to Prevent Gun Violence, 20 states - from Alaska to New Mexico - have introduced bills to allow specified or, in some cases, all permit holders to take their concealed weapons into school.
The centre, which is fighting these efforts, believes armed teachers would be more dangerous than helpful, increasing the likelihood of gun deaths and injuries.
The National Education Association (NEA) is also firmly opposed, calling the proposals "dangerous" and "misguided". In a recent poll, 68 per cent of the NEA's members were against arming teachers.
While the debate continues, so does the violence. In the month following Sandy Hook there were no fewer than five school shootings. In early January, a 16-year-old opened fire at his high school in Taft, California. A teacher and campus supervisor managed to talk him down. As NEA president Dennis Van Roekel noted, it was their "bravery and wisdom", not another gunman, that limited the injuries.