Big-city mayors and handgun-safety advocates have every right to be fed up with President Obama's track record so far on initiatives to help end the carnage from gun violence on the nation's streets.

Even in the aftermath of a number of grisly mass murders, the president made clear that his administration would not push to reinstate the assault-weapons ban that Congress and former President George W. Bush allowed to expire in 2004.

Now, Obama has taken a pass on repealing the Bush-era laws that shield gun traffickers and their suppliers. In cities such as Philadelphia and Camden, that's like reaffirming a death sentence for the hundreds of people slain each year by gunfire.

Last week, handgun-control advocates revealed that the president's 2010 budget reaffirms the so-called Tiahrt Amendment, which hamstrings law enforcement in tracing guns used in crimes.

The rules require records on gun background checks to be destroyed within 24 hours and bar law-enforcement officials from sharing gun-trace data with the public, advocates, or even criminal-justice scholars.

One good change proposed in the rules by Obama would free the hands of law-enforcement agencies somewhat in pursuing illegal gun deals, but the administration leaves most of the Tiahrt Amendment provisions in place.

"This policy has allowed guns to remain in the hands of hundreds of criminals," said Paul Helmke, president of the Brady Campaign to Prevent Gun Violence. Indeed, without good tracking data on handgun sales, police, federal authorities, and the public have a tough time learning "where the guns are going and which gun dealers are selling to traffickers," explains Bryan Miller, head of Ceasefire NJ.

The Tiahrt Amendment doesn't need to be tweaked; it needs to be scrapped - if the nation has any hope of stemming the flow of illegal guns. An updated assault-weapons ban should accompany that move, along with a federal ban on gun-show weapons sales without background checks. In New Jersey and Pennsylvania, monthly limits on legal handgun purchases should be enacted.

All of these gun-safety efforts deserve the president's full support.