His words have been eloquent and sympathetic, as they typically are when he is the voice of a nation in mourning.
But President Barack Obama's response to a gunman's massacre of 20 children and six adults at a Connecticut grade school has revealed a more complex view of the president: emotional, frustrated - and perhaps rethinking his largely hands-off approach to gun control.
"We can't tolerate this anymore," Obama said late Sunday at the vigil for the victims in Newtown, Connecticut, as he recalled earlier mass slayings and the shooting of former U.S. congresswoman Gabrielle Giffords in 2011. "These tragedies must end. And to end them we must change."
Obama notably did not use the word "gun," but he did cast his argument against violence in terms of another politically potent image: protecting America's children.
"Can we honestly say we're doing enough to keep our children, all of them, safe from harm?" Obama asked. "...If we're honest with ourselves, the answer's no. We're not doing enough and we will have to change."
Obama promised that "in the coming weeks, I'll use whatever power this office holds to engage my fellow citizens - from law enforcement to mental health professionals to parents and educators - in an effort aimed at preventing more tragedies like this."
It was the strongest signal yet that Friday's shootings and Obama's standing -- he was just returned to office and will not be up for election again -- may have inspired him to embrace gun control as part of his second-term agenda.
It is an issue around which Obama has stepped carefully during his first term and his re-election campaign, to the frustration of gun-control advocates.
Despite a series of mass killings by gunmen in recent years, polls have long indicated that most Americans are wary of increased restrictions on guns.
And the gun lobby, led by the National Rifle Association, has been a powerful force in building support among Republicans and rural Democrats, to the extent that trying to push new gun limits through Congress has been seen as a futile exercise.
But the slayings in Newtown, Connecticut, have given new momentum to calls for more limits on guns, including the reinstatement of a ban on the sale of "assault" weapons such as the semiautomatic rifle that gunman Adam Lanza used.
Sen. Dianne Feinstein, a California Democrat, said Sunday on NBC's "Meet the Press" that she will introduce a proposed ban on assault weapon