(CNN) It's been almost seven years since Congress came anywhere close to passing a serious gun control measure. The failure of that attempt, which came just months after the murder of more than two dozen people -- 20 of whom were children -- at Sandy Hook Elementary School in late 2012, provides a sobering reality check on the chances of the Senate passing any sort of gun control legislation in the wake of back-to-back mass shootings in El Paso, Texas, and Dayton, Ohio, last week.
Let's go back to that moment. It was the spring of 2013. The murders in Sandy Hook had seemed to galvanize the country -- and Congress -- to find a way to address the growing problem of mass violence committed with guns. Led by President Barack Obama and with 54 Senate seats controlled by Democrats, it appeared likely that Congress would pass the first major piece of gun control legislation since the assault weapons ban way back in 1994.
And then it all came crashing down in a single day.
The math seemed simple. Democrats needed all 54 of their senators plus six Republicans to avoid a filibuster of the gun legislation which, among other things, would have expanded background checks on gun purchases, banned certain types of assault rifles and limited ammunition magazines. For all of the talk -- and all of the meetings the parents of the children killed at Sandy Hook held with wavering senators -- it rapidly became apparent when the Senate began voting that the political will simply wasn't there to pass any of Obama's gun control proposals.
The most telling vote came on an amendment -- offered by Pennsylvania Republican Sen. Pat Toomey and Democratic West Virginia Sen. Joe Manchin -- that would have mandated expanded background checks and was seen as the piece of the Obama legislative offering on guns that had the best chance to succeed.
And it failed -- by a 54-46 vote. Then-Senate Majority Leader Harry Reid (Nevada) pulled the gun control legislation after that series of failed amendments. Obama, in one of the angriest moments he ever had as President, denounced the votes as "a pretty shameful day for Washington."
All told, eight senators crossed party lines in that background checks vote, with four Republican senators voting for it and four Democratic senators voting against it. Here they are:
* Republican "ayes": John McCain (Arizona), Mark Kirk (Illinois), Susan Collins (Maine) and Toomey (Pennsylvania)
* Democratic "nos": Max Baucus (Montana), Mark Begich (Alaska), Heidi Heitkamp (North Dakota) and Mark Pryor (Arkansas)
Of those eight, only two are currently senators: Collins and Toomey. McCain passed away in 2018. Kirk lost his reelection bid to Democratic Sen. Tammy Duckworth in 2016. And all four Democrats either retired (Baucus) or lost their seats to Republicans.
By any objective measure then, the current Senate -- where Republicans hold 53 seats -- is less friendly to new gun control legislation than the Senate of April 2013. And that 2013 Senate never even got even one part of the gun control legislative package passed the cloture stage. There was never a final up-or-down floor vote on any part of the package. None. And that was with a Democratic president pushing the legislation to a Democratic-controlled Senate.
So when you hear President Donald Trump say things like he supports expanded background checks and predicts the National Rifle Association is "going to get there also," you should be skeptical. When Senate Majority Leader Mitch McConnell promises that expanded background checks and so-called "red flag" laws will be "front and center" when the Senate returns after Labor Day you should take that promise cum grano salis.
The simple reality on the possibility of passing any sort of mildly major gun control measure -- like, say, expanded background checks -- is well less than 50% at the moment. What could change that dynamic? A high-profile -- and, more importantly, sustained -- effort by Trump and his White House to convince and cajole uncertain GOP senators to be for background check legislation. And there's little in Trump's past pronouncements on guns to believe that he is either willing or capable of that sort of effort.
At this point, it seems unlikely a major piece of gun control legislation will even advance as far as it did in 2013. And that wasn't very far.