President Obama has said there will be "shame" on himself and the American people if pledges to bring in tougher gun safety laws after the Newtown school massacre go unfulfilled.
More than 3,000 gun deaths have occurred in the US since Adam Lanza shot dead 26 children and staff at Sandy Hook Elementary School in Connecticut in December.
More shocking details of the speed of the attack and the arsenal of weapons Lanza owned have been released today.
But, as ITV News Correspondent Geraint Vincent reports from Washington, DC, Mr Obama still faces great difficulty in translating anger at the massacre into legislation aimed at curbing the public's right to bear the most powerful of arms.
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