The National Rifle Association's response to the Connecticut school shooting means any effort to pass new gun-control laws must overcome opposition from an organisation with longstanding clout in Congress.
NRA chief Wayne LaPierre on Friday dismissed calls for tighter gun limits and instead recommended armed school guards following the massacre of 20 children and six adults.
While not unexpected, the NRA's continued resistance to new firearms restrictions would make it more difficult to enact such measures, said Robert Spitzer, who has written four books on gun control.
"It's going to be a hard fight," Spitzer said. To overcome NRA opposition, Spitzer said, US President Barack Obama would have to spend some of the political capital he gained with his re-election last month.
"It's the ideal moment of any newly elected president to offer a new idea," said Spitzer. In addition, the Newtown killings, in which most of the victims were first-graders, "shocked people in a way that other mass shootings did not," he said. "When that happens, the NRA is at its low point of political influence."
Still, the NRA remains a formidable force, with four million members and a political advocacy arm that spent US$35 million on this year's election.
LaPierre rejected new restrictions on gun ownership and called for posting armed security guards at schools.
Politicians of both parties questioned the proposal.
"I don't necessarily think having armed guards outside of every classroom is the most conducive thing to a good educational environment," said New Jersey Governor Chris Christie, a Republican.
"We don't want to make this an armed camp. I don't think that would be positive."
Outside the hotel where LaPierre spoke, about 50 people gathered to demand that the NRA "stand down" from gun lobbying.
Congressman Chris Murphy, a Connecticut Democrat whose district includes Newtown, called the NRA response "the most revolting, tone-deaf statement I've ever seen" in a post on Twitter after leaving a victim's funeral.