NEW : During the Super Bowl on Sunday night , a group called Mayors Against Illegal Guns broadcast an ad showing the NRA 's LaPierre , in 1999 , endorsing the expanded background checks his group now opposes . Obama says no law can stop all gun violence , but the nation must try . NEW : Obama continues to call for reviving a ban on some weapons . New : Obama calls for universal background checks and an assault weapon ban. The focus on gun control is revived after the Connecticut school massacre .
NEW : Obama says no law can stop all gun violence , but the nation must try . NEW : Obama continues to call for reviving a ban on some weapons . New : Obama calls for universal background checks and an assault weapon ban. The focus on gun control is revived after the Connecticut school massacre .