The powerful National Rifle Association gun lobby has taken a no-retreat position, declaring that guns and police officers are needed in all American schools to stop the next killer "waiting in the wings".
Wayne LaPierre, the group's chief executive, took the defiant stance in a speech amid growing calls for gun control after the Connecticut school massacre that claimed the lives of 26 children and school staff.
Some members of Congress who had long scoffed at gun-control proposals have begun to suggest some concessions could be made, and a fierce debate over legislation seems likely next month. President Barack Obama has demanded "real action, right now".
That has left the largest United States gun-rights lobby on the defensive. It broke its week-long silence on the shooting rampage in an event billed as a news conference, but with no questions. Twice it was interrupted by banner-waving protesters, who were removed by security.
"The only thing that stops a bad guy with a gun is a good guy with a gun," said LaPierre.
Some had predicted that after the slaughter of so many children by a man using a semi-automatic rifle, the group might soften its stance. Instead, LaPierre delivered a 25-minute tirade against the notion that another gun law would stop killings in a culture where children are exposed daily to violence in video games, movies and music videos.
He argued that guns are the solution, not the problem.
"Before Congress reconvenes, before we engage in any lengthy debate over legislation ... We need to have every single school in America immediately deploy a protection programme proven to work," LaPierre said. "And by that I mean armed security."
New York City Mayor Michael Bloomberg said the NRA was blaming everyone but itself for a national gun crisis and was offering "a paranoid, dystopian vision of a more dangerous and violent America where everyone is armed and no place is safe".
Meanwhile, LaPierre said the NRA would develop a school emergency-response programme that would include volunteers from the group's 4.3 million members to help guard children.
His idea was immediately lambasted by gun-control advocates, and not even the NRA's point man on the effort seemed willing to go so far. Former Republican Congressman Asa Hutchinson of Arkansas, whom LaPierre named national director of the programme, said in an interview that decisions about armed guards in schools should be made by local districts.
"I think everyone recognises that an armed presence in schools is sometimes appropriate," Hutchinson said.
Hutchinson said he would offer a plan next month that will consider other measures such as biometric entry points, patrols and consideration of school layouts.
LaPierre argued that guards needed to be in place quickly because "the next Adam Lanza", the suspected shooter in Newtown, Connecticut, is already planning an attack on another school.
Democratic Congressman Jerrold Nadler of New York called the NRA's response "both ludicrous and insulting", and pointed out that armed personnel at Columbine High School in Colorado and the Fort Hood Army post in Texas could not stop mass shootings.