Almost immediately after a gunman in Las Vegas mowed down dozens of people and injured hundreds of concert-goers last fall, there was unprecedented openness among many Republicans in Congress for some kind of gun control legislation.
Yet more than four months after the deadliest shooting in modern U.S. history, Congress has yet to send any firearm-related bill aimed to curb gun violence to the President's desk.
On Wednesday, 17 people were killed at a Florida high school, invoking the same sense of fury and outrage seen time and time again, as Washington once more became the epicenter for the emotional debate over how to break a continuous loop of massacres.
"Can you tell us," California Democratic Rep. Mike Thompson said on the House floor Thursday, as some of his colleagues cheered him on, "when the House may muster the courage to take up the issue of gun violence?"
House Minority Leader Nancy Pelosi said gun control bills are more important to her than her seat in Congress.
"I have said it over and over: I would rather pass gun safety legislation than win the election, because people die from this," she told reporters.
Hitting congressional leadership for its unwillingness to take up the issue, she said, "Children are dying in our schools, in our communities, on our streets. All this Congress has to say is 'let's have a moment of silence.'"
Senate leaders held a moment of silence for the victims in Florida, but there was no plan as of early Thursday afternoon by Republicans who control Congress to take any legislative action.
The standstill reflects a fundamental difference between most Democrats and most Republicans on the question of gun control. Republicans -- for both political realities and their core beliefs -- don't see restrictions on guns as the answer to gun violence.
"I want to begin this morning by sharing the shock and sorrow that all of us in this body felt as we learned of yesterday's shooting," Senate Majority Leader Mitch McConnell said on the Senate floor. "To say that such brutal, pointless violence is unconscionable is an understatement. Schools should be places where children can learn, and faculty and staff can work, without fear of violence."
After Las Vegas
There was some action related to gun violence in Congress last fall, but nothing has been passed into law. While there's no evidence that these efforts would have prevented the Florida shooting, pro-gun control activists and many Democrats are desperately pleading for Congress to take any kind of action related to gun violence.
Just days after the Las Vegas shooting in October, a bipartisan group of lawmakers introduced legislation to ban the sale of bump fire stocks, a type of a device that enables semi-automatic rifles to fire more rapidly, similar to automatic weapons. Twelve of them were found on firearms recovered from the gunman's hotel room.
The bill has gone nowhere, as Republicans instead have largely decided to defer to the Bureau of Alcohol, Tobacco, Firearms and Explosive to make a regulatory change rather than pursue a legislative one in Congress. That removes the issue from a politically toxic environment in Congress, where a legislative fix would be uncertain.
The rulemaking process kicked off in December. The estimated timeline for a ruling, congressional sources told CNN, is eight to 12 months.
Also, the House passed legislation in December that would direct the Bureau of Justice Statistics to study all crimes involving firearms and report back to Congress in six months about how many involved weapons with bump stocks.
A little more than a month after Las Vegas, a gunman killed 26 people at a church in Texas. The shooter had previously been imprisoned for domestic abuse, but the Air Force didn't convey that information to the National Instant Criminal Background Check System, which should have prevented him from buying the guns used in the mass shooting.
That provoked bipartisan support for legislation that would improve the background check system to ensure that states and the federal government upload required background check information into the system.
While the House passed a bill that included this provision in December, a Senate bill with the same proposals -- sponsored by Murphy and Sen. John Cornyn, the No. 2 Republican in the Senate -- has stalled. It's been referred to the Judiciary Committee, but it has not been taken up for a vote.
"That bill is sitting over in the Senate. So, it's not as if nothing has been done to enforce the laws we have in the books and make sure that people, bad people who aren't supposed to get guns don't get guns," House Speaker Paul Ryan said Thursday in a radio interview with WIBC out of Indiana.
However, Ryan added, "I don't think that means you then roll the conversation into taking away citizens' rights, taking away a law abiding citizen's' rights."
Sen. Chuck Grassley, who chairs the Judiciary Committee, weighed in on the Florida shooting Thursday, though he did not speak specifically about the background check related bill.
"It seems to be common for a lot of these shootings, in fact almost all of the shootings, is the mental state of the people," the Iowa Republican said. "And we have not done a very good job of making sure that people that have mental reasons for not being able to handle a gun getting their name into the FBI files, and we need to concentrate on that."
Sen. Dianne Feinstein, D-California, said she and Grassley are hoping to sit down with GOP whip John Cornyn about bump stock legislation.
Pro-gun control activists and many Democrats in Congress were furious in December when the House approved legislation that would loosen gun regulations and allow those with permits to carry concealed weapons to legally travel with those firearms to other states, a top priority of the National Rifle Association.