"It's time for the president to . . . lead and tell this country what we should do, not go to Congress and say, 'What do you guys want to do?' " Bloomberg said, speaking on NBC's "Meet The Press" about the fatal assault Friday on a Connecticut school.
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He noted that Obama campaigned in 2008 on an assault weapons ban. "The only gun legislation that the president has signed since then was one that gave the right to carry a gun in national parks, where our kids play, and one that gave the right to carry guns on Amtrak . . ." Bloomberg said.
A shooting such as the one in Newtown, Conn., where 27 people were killed, including 20 first-graders, "only happens in America. And it happens again and again," he said. "We've just got to stop this . . . We don't need military assault weapons with big magazines on the streets of our cities."
Bloomberg called for new legislation banning assault weapons with large magazines. And he called for a law that would close a loophole that allows people to buy and sell weapons at gun shows without undergoing background checks.
Also on "Meet The Press," Connecticut Gov. Dannel Malloy said part of the solution is better care for the mentally ill. But Malloy also noted that Congress allowed the ban on assault weapons to lapse in 2004. And Democratic Sen. Dianne Feinstein of California said on the show that she'll revive her plan to ban new assault weapons.
"This should be his No. 1 agenda" during his second term, Bloomberg said of Obama, who he noted was re-elected despite opposition from the NRA. "If he does nothing during his second term, something like 48,000 Americans will be killed with illegal guns. That is roughly the number of Americans killed in the whole Vietnam War."
The NRA could not be reached and its website made no mention of the shooting. But Gun Owners of America, a Springfield, Va., lobbying group, has since called for the repeal of the Federal Gun Free Schools Zone Act, saying that because the law forbids most adults working in schools to carry firearms on the premises, they can't protect themselves and their students from attackers.
The White House offered no response.
"Nobody questions the Second Amendment's right to bear arms," the mayor said. "I don't think the founding fathers had the idea that every man, woman and child could carry an assault weapon."
Despite the chorus of calls for gun-control reform, Rep. Peter King (R-Seaford) said Sunday he was "not hopeful" that legislation would pass through Congress, given similar failed attempts for reforms following previous mass shootings.
"Based on what I've seen over the last 10 years, I'm not hopeful," King said. "In the last several years, we've seen Virginia Tech, Gabby Giffords, the shooting at a movie theater in Colorado and countless others, but there continues to be opposition."
King said he is a proponent of "meaningful" reform and voted in favor of the assault weapons ban back in 1994. He has sponsored a measure to prevent those on the federal terrorist watch list from purchasing weapons.
Meanwhile, McCarthy, a Mineola Democrat whose husband was killed and son wounded during an assault on passengers on a Long Island Rail Road train in 1993, said on CNN, "The attitudes of the American people are a little bit different than they were on Friday."
McCarthy also wrote to Obama on Sunday asking for action to improve the background-check system. "I ask you to immediately improve the flow of information into the system by requiring all federal agencies to share relevant information," she wrote.
With Laura Figueroa, AP and Scripps Howard News Service