San Francisco CNN —  

Making his second call in as many days for tighter gun control laws, President Barack Obama on Friday told a crowd of mayors it was again time for a national conversation on the scourge of mass shootings in America.

“We need a change in attitude,” Obama said in remarks to the annual meeting of the U.S. Conference of Mayors in San Francisco. He said the country was “shocked and heartbroken” by the shooting deaths of nine churchgoers in Charleston, South Carolina this week.

The morning after the shooting, Obama made a direct and personal call for bolstering gun control laws from the White House, admitting the current balance of power in Washington makes any meaningful action unlikely.

But he said on Friday he wasn’t resigned to inaction in Congress.

“We have to move public opinion,” Obama said. “We have to feel a sense of urgency. Ultimately Congress will follow the people.”

RELATED: Obama, Clinton press for greater gun restrictions in wake of church massacre

Obama last made a push to tighten gun control laws in the aftermath of the shooting at Sandy Hook Elementary School in 2012. A measure that would have expanded background checks during gun sales gained bipartisan support, but ultimately failed to surpass a filibuster in the Senate.

While the Obama administration enacted nearly two dozen executive actions meant to improve gun safety, the issue has largely been dormant on Capitol Hill since.

On Friday, Obama said the lack of action in Washington wasn’t an excuse to ignore a problem he noted took the lives of 11,000 Americans in 2013 alone.

“I refuse to act as if this is the new normal or to pretend that it’s simply sufficient to grieve and that any mention of us doing something to stop it is somehow politicizing the problem,” he said.

The President suggested that tighter gun laws can be passed despite a lack of bipartisan support from Congress.

“We have to shift how we think about this issue and we have the capacity to change, but we have to build a sense of urgency about it,” he said. “That’s how we honor those families (in Charleston). That’s how we honor the families of Newtown, and that’s how we honor the families in Aurora.”

In his speech to mayors, the President acknowledged the racist motivations of Dylann Roof, who sources say admitted to shooting nine people at the historic Emanuel African Methodist Episcopal Church on Wednesday night.

Roof, according to witnesses, told his victims that he came to “shoot up black people.”

“The apparent motivations of the shooter remind us that racism remains a blight that we have to combat,” Obama said on Friday. “We have made great progress, but we have to be vigilant because it still lingers.”

Violent acts – often committed by young people – “betrays our ideals and tears our democracy apart,” he said, adding later that other countries, despite confronting similar mental health problems, “don’t see murder on this kind of scale, with this kind of frequency.”

“At some point as a country, we have to reckon with what happens. It is not good enough simply to show sympathy,” he said.

The President’s comments came on the same day he issued a statement on the 150th anniversary of Juneteenth, when the abolition of slavery was announced in Texas.

“We don’t have to look far to see that racism and bigotry, hate and intolerance, are still all too alive in our world,” he said.

Obama was speaking in the middle of a four-day swing through California. On Thursday, he began his trip with two fundraisers hosted by Hollywood heavyweights: actor and filmmaker Tyler Perry and television writer Chuck Lorre.

Addressing the shootings at Perry’s house, Obama told the crowd of 250 Democratic donors if they were “dissatisfied that every few months we have a mass shooting in this country, killing innocent people, then I need you to mobilize” and help elect pro-gun control politicians.

Later on Friday, Obama will attend a fundraiser for Congressional Democrats at the San Francisco home of climate change activist Tom Steyer.

Following the two fundraisers, the President will spend the rest of Father’s Day weekend in his favorite desert oasis, Palm Springs, where he is expected to golf.

Allison Malloy reported from San Francisco. Kevin Liptak and Eugene Scott reported from Washington.