As I noted earlier, yesterday’s Senate votes on the Manchin-Toomey amendment as well as other provisions ended the chances that any gun control legislation will pass Congress this year. While Democrats like House Minority Leader Nancy Pelosi and California Senator Dianne Feinstein have vowed to keep pushing for assault weapon bans and other proposals that have zero chance of passage, from this point forward the debate will be conducted solely with an eye toward public opinion and next year’s midterm election, not any specific legislation. That means that while some may dismiss yesterday’s bitter post-vote comments by President Obama and other gun control advocates as mere posturing, they are actually quite significant.

Obama, former Representative Gabrielle Giffords and other supporters of various new restrictions were not shy about lambasting the National Rifle Association during the last four months. The Newtown massacre gave the White House an excuse to resurrect gun control as a national issue, yet he was sufficiently interested in attracting the votes of wavering members of Congress that he tended to restrict his demagoguery to the stock villains of the National Rifle Association leadership. But yesterday’s defeat changed all that. The rejection of Manchin-Toomey has set off a wave of almost hysterical denunciations of gun rights advocates from Obama, Giffords and media figures like MSNBC’s Joe Scarborough and Mika Brzezinski today that has lowered the discourse on the issue to a level that has rarely been seen before. After spending much of the last few years accusing right-wing Tea Party members of incivility that was at the heart of the dysfunction of our political system, liberals have now raised the stakes in this game to a point where dialogue is now impossible.

I think the Toomey-Manchin proposal was a reasonable compromise that Republicans should have embraced, if only because it could have put this issue to rest without compromising Second Amendment rights. But the refusal of many conservatives as well as some Democrats to accept this idea was not entirely the fault of NRA pressure tactics. The reason why so many that care about gun rights thought of Manchin-Toomey as the thin edge of the wedge of an effort to undermine the Second Amendment was because so many liberals made it clear that was their intention. While the NRA may have mischaracterized Manchin-Toomey, there was little doubt most liberal Democrats considered even an assault weapons ban as just the start of their efforts to make it harder to legally own weapons in this country.

One may consider this belief to be mistaken, but what has happened in the last 24 hours is that liberals have decided this issue is no longer one on which reasonable people can disagree. Today, Ms. Giffords published an op-ed in the New York Times in which she framed those who would not support gun legislation as not caring about keeping children safe. One of the Newtown victim family members went on MSNBC and said senators who didn’t vote as she liked didn’t care about those who died in the massacre. MSNBC’s “Morning Joe” hosts Scarborough and Brzezinski, who have used their popular show to campaign non-stop for gun legislation, similarly sought to stigmatize opponents and, as usual, offered no rationale offered for the failure of the bill other than the lack of character by the 46 Senators who opposed it.

There are two points that must be emphasized here.

One is that the language used by these people as well as the president who lashed out at his antagonists as liars and cowards wasn’t merely frustration; it was an effort to demonize opponents. Doing this pretty much puts an end to an effort to conduct dialogue on these issues or to convince people. Confident that they represent the majority, they are now solely intent on branding anyone who opposed these bills as not just wrong, but bad people.

Second is that by employing shooting victims in this manner, the president is actually minimizing their impact on the discussion. So long as the Newtown families or others associated with other such crimes remain above the fray, their status is akin to that of national heroes. But by injecting themselves into what is becoming a nasty partisan argument they have become just another set of talking heads. As Kevin Williamson said of Giffords on National Review’s website today, “being shot in the head by a lunatic does not give one any special grace to pronounce upon public-policy questions.”

That may sound insensitive, but it points out that while she and the Newtown relatives are entitled to a respectful hearing, their story does not give them the right to expect that everyone in the country must agree with their pronouncements on political issues. That is especially true since the great failure of the administration over these past few months was its inability to draw any specific link between any of the measures they proposed and the Newtown tragedy.

The 46 members of the Senate who opposed Manchin-Toomey will not, as Giffords wants, be put into Coventry and shunned by their constituents. Nor, as Scarborough suggested, will they all be defeated when they run for re-election. But the one thing we do know is that this sort of rhetoric has made it even less likely that the country can hold a civil debate on guns. For all of its mistakes, that is one unsettling development that can’t be blamed on the NRA.