President Barack Obama on Wednesday urged Congress to pass sweeping new gun controls including universal background checks on anyone purchasing a weapon and reinstating a ban on military assault style weapons.

“This is common sense,” the president said during a press conference at the White House. “There’s no reason we can’t do this.”

Barely a month after 20 children and six adults were killed by a gunman armed with an automatic weapon at an elementary school in Newtown, Ct., the president has apparently decided to make gun control a central theme of his second term.

The National Rifle Association and other opponents to restrictions on gun ownership are certain to fight back hard against the proposals.

In addition to his broad recommendations that need Congressional approval, Obama signed an executive action calling for 23 steps that don’t need Congress’s OK. They include tighter background checks, eliminating a ban on federal research into gun violence, adding counselors and "resource officers" to school staffs and making access to mental health services easier.

Obama announced the new legislative measures at a news conference attended by four children who wrote letters to the White House in the wake of the Newtown shooting and who asked the president to act on gun control, an issue he did not address materially in his first term.

During a 10-minute speech, the president also invoked recent mass shootings in a movie theater in Aurora, Colo., and at a mall outside Portland, Ore. Also in attendance were parents of children killed in the Newtown shooting.

In addition to mandatory background checks and a ban on military assault style weapons, Obama called for a ban on the sale of magazines that hold more than 10 rounds. In the Newtown and Aurora shootings, the gunmen each used magazines holding 30 rounds of ammunition, allowing them to kill and injure dozens of people in a matter of seconds.

The president acknowledged his proposals won’t be easy to pass. “This will be difficult,” he said. “This will not happen unless the American people demand it.”

The new effort to pass gun control legislation was spearheaded by Vice President Joe Biden, who chaired a committee put together by the president in the days following the Dec. 14, Newtown shooting.

Since then Biden has met with a range of groups whose contributions were sought in an effort to stem the violence. The group included members of law enforcement, gun makers and sellers, and entertainment figures from the movie and video game industries.

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