WASHINGTON -- Now that President Barack Obama has demanded "real action, right now" against U.S. gun violence, attention turned Thursday to the coming "major news conference" by the country's top gun lobby, whose power for years has contributed to the political hesitation around the issue.

The National Rifle Association, which was silent for several days after last week's school shooting in Connecticut, has promised to make its announcement Friday -- the last real work day before Washington, and the rest of the country, scatters for the long Christmas holiday.

Obama has asked the NRA, a key backer of many Republican politicians, to join the effort to reduce gun violence. Moving quickly after several congressional gun-rights supporters said they would consider new legislation to control firearms, the president said Wednesday he wants proposals on reducing gun violence that he can take to Congress by January.

Obama's insistence is a sharp contrast with his first four years in office, when he pressed little on the issue amid widespread political reluctance to take on the NRA and smaller lobbying groups.

The president acknowledged that the latest shooting, where children as young as 6 were shot multiple times at close range with a high-powered rifle, had been "a wake-up call for all of us." Appealing to gun owners, he said he believes in the constitutional right to bear arms and the country's strong tradition of gun ownership.

"I am also betting that the majority, the vast majority, of responsible, law-abiding gun owners would be some of the first to say that we should be able to keep an irresponsible, law-breaking few from buying a weapon of war," Obama said.

But a generation of U.S. gun laws -- and the compromises that have been made to balance constitutional gun rights and public safety -- reflects the challenges ahead in applying government policy to stem acts of mass violence.

Along with asking Congress to reinstate an assault weapons ban that expired in 2004, Obama asked lawmakers to pass legislation that would close the gun show "loophole," which allows people to purchase firearms from private dealers without a background check. Obama also said he wanted Congress to pursue the possibility of limiting high-capacity ammunition clips.

Police say last week's school shooter, 20-year-old Adam Lanza, needed just 10 minutes to shoot and kill 20 children and six adults. He also killed his mother and himself. Funerals continued Thursday for the victims.

The past assault weapons ban would have made it illegal for Lanza to use the 30-round magazines that allowed him to shoot so many children before he reloaded. But the ban and other gun laws wouldn't have prevented his mother's purchase of the powerful assault rifle or the especially deadly ammunition that he used. And federal laws wouldn't have affected Lanza's access to them

The past ban outlawed the new manufacture and sale of specific named weapons, including the Colt AR-15, UZI and TEC-9, and high-capacity magazines and clips that held more than 10 bullets. But it didn't ban any class of weapons based on the size and type of bullets used, including the types of high-powered weapons used in the most recent mass killings. It also permitted the resale of used weapons and clips manufactured prior to 1994.

Also, federal law bars someone who "has been adjudicated as a mental defective or has been committed to any mental institution" from buying a gun. Yet Jared Loughner, who pleaded guilty earlier this year in the deadly 2011 mass shooting that also wounded then-Rep. Gabrielle Giffords in Arizona, was not ruled by a court to be mentally ill before the attack.

Tom Diaz, a senior policy analyst at the Violence Policy Center, said lawmakers should focus on a weapon's firepower. In this year's deadly Colorado theatre shooting and last week's deadly attack at an Oregon mall, police said the accused shooters used AR-15 assault rifles, versions of which were outlawed under the 1994 ban.

Diaz said bullets fired from those types of guns are powerful enough to pierce all but the highest-grade, military-style, bullet-proof vests.

"It's designed for battlefield use," Diaz said.