When a somber President Obama spoke Thursday about the mass shooting in Charleston, he said, "I've had to make statements like this too many times." He added: "Once again, innocent people were killed in part because someone who wanted to inflict harm had no trouble getting their hands on a gun."

Indeed, when he spoke about the issue last year, he went even further — calling a lack of action on guns the single biggest disappointment of his presidency. He made the remarks in a Q&A with the CEO of Tumblr:

OBAMA: People often ask me how has it been being President, and what am I proudest of and what are my biggest disappointments. And I've got two and a half years left. My biggest frustration so far is the fact that this society has not been willing to take some basic steps to keep guns out of the hands of people who can do just unbelievable damage.

His choice of gun control last year was particularly interesting given Obama's history on the issue. He deliberately downplayed the gun issue during his first presidential campaign, not wanting to alienate rural or swing voters. And once he was sworn in, he continued with that basic approach — many Senate Democrats were from red states with strong gun rights cultures, and Obama needed their votes for his health-care and financial reform legislation. Even after the shooting of Representative Gabrielle Giffords (D-AZ) in January 2011, Obama didn't do very much.

"20 six-year-olds were gunned down in the most violent fashion possible, and this town couldn't do anything"

But once Adam Lanza murdered 20 children and six adults at Sandy Hook Elementary School in Newtown, Connecticut, Obama was shaken — tearing up in a public statement. He decided to make a push for tougher gun laws a central part of his second-term agenda.

Yet the Democrats' proposals — reinstating the ban on assault weapons, expanding background checks, and limiting high-capacity magazines — ended up filibustered by Senate Republicans, and never even got a vote in the GOP-controlled House. Any congressional action on the issue now appears unlikely, particularly after the GOP takeover of the Senate.

"I have been in Washington for a while now, and most things don't surprise me," Obama said in the Q&A, but "the fact that 20 six-year-olds were gunned down in the most violent fashion possible and this town couldn't do anything about it was stunning to me." He continued, "The country has to do some soul searching about this. This is becoming the norm, and we take it for granted in ways that, as a parent, are terrifying." But because of the power of organized interest groups like the NRA, he said, "until there's a fundamental shift in public opinion… not much is going to change."