On "Meet the Press" this morning, Mayor Bloomberg put pressure on President Obama and Congress to enact gun control legislation in the wake of the Newtown slayings, specifically the federal ban on assault weapons that expired in 2004. "It’s time for the president, I think, to stand up and lead and tell this country what we should do. Not go to Congress and say what you guys want to do," Bloomberg said. "The president campaigned back in 2008 on a bill that would prohibit assault weapons. We’ve got to really question whether military-style weapons with big magazines belong on the streets of America in this day and age."

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Bloomberg's gun control coalition, Mayors Against Illegal Guns, has a petition to "Demand a Plan" for gun control, and New York Governor Andrew Cuomo also called for a "crack down" on assault weapons. Connecticut Governor Daniel Malloy noted that it's time for the country to reassess how we treat the mentally ill, and expressed disappointment that the ban on assault weapons was ever allowed to lapse.

The alleged shooter, 20-year-old Adam Lanza, killed 27 people on Friday morning before killing himself, using a .223-caliber Bushmaster rifle that belonged to his mother, Nancy Lanza, a reported gun enthusiast. Lanza killed his mother before heading to Sandy Hook Elementary School. The Bushmaster rifle Lanza used is a semi-automatic assault weapon that can shoot six bullets in one second.

Yesterday, President Obama's press secretary told reporters that an assault weapons ban "does remain a commitment of his." During a presidential debate on October 16, Obama expressed support for "seeing if we can get an assault weapons ban reintroduced."

FOX News warned that the remark would cost him voters, a concern that seems especially overblown, and one that Bloomberg outright dismissed this morning: “The N.R.A.’s No. 1 object this time was to defeat Barack Obama for a second term…This myth that the N.R.A. can destroy political careers is just not true.”

However, the NRA's ability to intimidate Congressional leadership in preventing gun control legislation is not a myth, as the organization has consistently out-fundraised gun control proponents and has been emboldened by a series of court rulings, most notably D.C. vs. Heller, which for the first time ruled that the Second Amendment protects an individual's right to bear arms in a federal enclave.

A subsequent ruling affirmed that the 2nd Amendment is applied to the states, but in a dissent, Justice Stephen Breyer noted "The Framers did not write the Second Amendment in order to protect a private right of armed self defense. There has been, and is, no consensus that the right is, or was, 'fundamental.' " This view was also advanced by former Chief Justice of the Supreme Court Warren E. Burger. A conservative appointed by Richard Nixon, Burger said in a 1991 interview that the Second Amendment "has been the subject of one of the greatest pieces of fraud, I repeat the word fraud,' on the American public."

Yet during his first term as president, Obama has done nothing to advance gun control legislation, and according to the Brady Campaign [PDF], has signed more repeals of federal gun control policies than George W. Bush did. Former Obama chief-of-staff and current Mayor of Chicago Rahm Emanuel reportedly told Attorney General Eric Holder that he needed to "shut the fuck up" after Holder repeated Obama's campaign promise to enact an assault weapons ban.

California Senator Diane Feinstein also appeared on Meet the Press to announce that she would introduce an assault weapons ban in the Senate at the beginning of the new Congressional session in January. "It will ban the sale, the transfer, the importation and the possession," Feinstein said. "And it will ban the same for big clips, drums or strips of more than 10 bullets."

But Bloomberg said that the president could and should take action right now:

What the president can do is, No. 1, through executive action, he can order his agencies to enforce the laws more aggressively. There were something like 77,000 people who’ve been accused of lying when they applied for a gun permit. We’ve only prosecuted 77 of them.

President Obama is scheduled to speak at an interfaith vigil for the victims of the shooting tonight in Newtown at 7 p.m.