Bristling with anger, President Barack Obama branded Wednesday's defeat of gun reform in the US Senate as "shameful," accused lawmakers of caving to the gun lobby, and promised to fight on.
A deeply emotional Obama -- using disdainful language, and surrounded by relatives of gun victims, including some of the 20 kids gunned down in the Newtown massacre -- accused the firearms lobby of lying to halt change.
He spoke after a bid to expand background checks for gun buyers, the most significant remaining effort to change gun laws since the school killing last year, was blocked in the Senate by Republicans and conservative Democrats.
"Families that know unspeakable grief summoned the courage to petition their elected leaders not just to honor the memory of their children but to protect the lives of all of our children," Obama said.
"A minority in the United States Senate decided it wasn't worth it," the president said in the White House Rose Garden, as he absorbed the first significant political defeat of his second term.
"The gun lobby and its allies willfully lied about the bill," said Obama, who was clearly furious about the vote, months after vowing to use all his power to enact gun reform in the tearful aftermath of the Newtown tragedy.
"All in all, this was a pretty shameful day for Washington."
In a scathing rebuke, Obama complained that Republicans and some of his own Democrats had simply been scared of the wealthy gun lobby.
"They caved to the pressure. And they started looking for an excuse, any excuse to vote no," Obama said, vowing to fight on for change.
"I see this as just round one," he said.
"I believe we're going to be able to get this done, sooner or later we're going to get this right. The memories of these children demand it."
Republicans argued that the bill infringed on the constitutional right to bear arms, but Obama said it did no such thing and merely tried to stop criminals and the mentally ill from getting firearms.
Chris Cox, chief lobbyist for the National Rifle Association, the top pro-gun pressure group, said the background checks bill was "misguided" and would have criminalized transfers of arms between honest citizens and friends.
"Expanding background checks, at gun shows or elsewhere, will not reduce violent crime or keep our kids safe in their schools," Cox said.
Obama's calls for a reinstated ban on assault weapons and high-capacity magazine clips were already certain to fall on deaf ears in the Senate.
The background checks bill attracted a majority vote -- 54-46 -- but 60 senators were needed for passage.
After the measure went down, one gun violence survivor, Patricia Maisch, shouted "Shame on you!" from the Senate gallery.
Maisch was at the 2011 shooting that left six people dead and then-congresswoman Gabrielle Giffords gravely wounded in Arizona.
Giffords was at Obama's side in the White House Rose Garden, along with Vice President Joe Biden and traumatized parents of several Newtown children.
"They have no souls, they have no compassion for the experiences that people have lived through (with) gun violence, who have had a child or a loved one murdered by a gun," Maisch said.
Obama was incensed by claims by some conservatives that he had used relatives of victims as political props in the campaign debate.
"Do we really think thousands of families whose lives have been shattered by gun violence don't have a right to weigh in on this issue?" he said.
Before Obama spoke, Mark Barden, whose seven-year-old son Daniel died at Sandy Hook Elementary School in Newtown, promised to carry on the battle.
"We will not be defeated and we are not defeated. We are not going away," he said, as he fought back tears.
The vote showed that US lawmakers remain deeply apprehensive about instituting any legislation that could be seen as infringing on Americans' constitutional right to bear arms.
Shortly before the vote, one Republican Senator, John McCain, announced his backing, but knew the amendment was already doomed.
"You did the right thing," he told his colleague Joe Manchin, who helped write the background checks bill.
"Sooner or later, this country will take up this issue," McCain added.
Polls show that 90 percent of American back closing the loophole that allows people to purchase firearms at gun shows with no background check.