Two months after the mass shooting in Arizona, President Obama is calling for better background checks on gun buyers and suggesting that more gun control legislation may be needed.

"Clearly, there's more we can do to prevent gun violence," Obama said in an op-ed for the Arizona Daily Star in Tucson, site of the Jan. 8 shooting that killed six and wounded 13, including Rep. Gabrielle Giffords, D-Ariz. "But I want this to at least be the beginning of a new discussion on how we can keep America safe for all our people."

Obama did not offer specifics, but did anticipate the political difficulties of enacting new gun legislation.

"Some will say that anything short of the most sweeping anti-gun legislation is a capitulation to the gun lobby," Obama wrote, while "others will predictably cast any discussion as the opening salvo in a wild-eyed scheme to take away everybody's guns."

But Obama expressed confidence that "most gun-control advocates know that most gun owners are responsible citizens" and that "most gun owners know that the word 'commonsense' isn't a code word for 'confiscation.'''

"None of us should be willing to remain passive in the face of violence or resigned to watching helplessly as another rampage unfolds on television," Obama wrote.

The president did not mention accused Tuscon shooter Jared Loughner by name, but wrote that "a man our Army rejected as unfit for service; a man one of our colleges deemed too unstable for studies; a man apparently bent on violence, was able to walk into a store and buy a gun."

In calling for better background checks, Obama wrote:

-- "The National Instant Criminal Background Check System is the filter that's supposed to stop the wrong people from getting their hands on a gun. Bipartisan legislation four years ago was supposed to strengthen this system, but it hasn't been properly implemented."

-- "We should in fact reward the states that provide the best data - and therefore do the most to protect our citizens."

-- "We should provide an instant, accurate, comprehensive and consistent system for background checks to sellers who want to do the right thing, and make sure that criminals can't escape it."