There has been a lot of chatter out there to the effect that the “moment may have passed” for real legislative action in the wake of the slaughter of 20 children in Newtown. It’s all nonsense. If no meaningful action takes place — which is certainly a real possibility — don’t blame waning public sentiment for it. Blame the cowardice of our lawmakers.

Today Obama will hold an event with mothers at the White House to keep up the pressure on members of Congress, and gun reform advocates are holding similar events in multiple states across the country. As the White House and gun reformers well understand, it is critical to keep the need for reform in the headlines.

The notion that public sentiment is fading is based on a few recent polls that found slippage in support for the general idea of restrictions on guns. But the fact remains: Support for the actual policies being proposed remains overwhelming. Polls by the Post and Quinnipiac taken this month — well over three months after the Newtown shootings — both found that roughly nine in 10 Americans support universal background checks, the centerpiece of Obama’s gun package.

So the public’s appetite for legislative action to combat gun violence is still there. The problem lies with our lawmakers. A number of red state Dem Senators are still refusing to say whether they will back expanded background checks, and Republicans who support that as a general policy goal — such as Tom Coburn — continue to withhold support for the proposal over bogus concerns about record keeping. Dem Senators Joe Donnelly and Kay Hagan are now indicating they’re generally supportive of the idea, which suggests some movement. But this simply isn’t good enough. Where are Kay Hagan, Mark Pryor, Heidi Heitkamp, and Mary Landrieu? The time to declare independence from the NRA is right now. As Michael Tomasky writes:

These … Democrats, along with their fellow red-staters, need to stand as one and say to the NRA that something that’s so common-sense, that was good enough for Tom Coburn (assuming that turns out to be the case), that is supported by a majority of their voters, is something they are going to support, period. And they’ll win. Democrats need to learn that you’re far better off taking a stand than looking like a water-carrier. The NRA is never going to love them anyway. If some Democrats in red states can go against the group and win, gun politics will change.

The site of Democratic Senators stampeding forth to declare support for marriage equality before it’s too late, getting in just under the wire of history now that it’s politically easy, was dispiriting enough, and serves as a cautionary tale. Do Democrats really want to be on the wrong side of history on an issue in which the lives of children are at stake? Let’s say lawmakers punt, and down the road there’s another horrific massacre in which more children are slaughtered — one that could have been prevented. What then, Democrats? Isn’t that outcome a good deal more frightening to you than the prospect of political pressure from the NRA?

* Keeping up the pressure on guns: Mike Bloomberg’s group, Mayor’s Against Illegal Guns, has unveiled a new ad featuring parents of slain Newtown children demanding that Connecticut pass stricter gun controls, including a universal background check. This quote from one family member says it all:

“Don’t let the memory of Newtown fade without doing something real.”

Cue up the right’s claims that these parents are allowing themselves to be used as “political props.”

* SCOTUS set to punt on gay marriage: Ron Brownstein has a good piece detailing how the quest for marriage equality will be marred by a deep nationwide partisan split, in which gay marriage will be legal in blue states, and illegal in red ones, if the Supreme Court doesn’t issue a ruling that creates a constitutional standard on discriminatory laws.

Unfortunately, as I detailed here yesterday, such a standard appears unlikely, based on what we saw before the Court this week.

* Immigration reform set to move forward: Obama has told a Spanish language station that he believes the bipartisan Senate “Gang of Eight” will produce an immigration compromise early next month, and that it will be voted on in the Senate by the end of April. If so, it will be another reminder of how quickly the GOP’s brush with demographic doom has prompted a shift on the issue.

* A great moment from the SCOTUS DOMA hearing: Rachel Maddow had a terrific segment last night highlighting a key moment in the DOMA arguments, in which Chief Justice John Roberts suggested that discrimination against gays was mitigated by the fact that the gay rights “lobby” is politically powerful. The pushback from Edith Windsor’s lawyer — who noted that no other group has been subjected to popular referenda to take away rights already granted it — was a thing of beauty.

 * Gay marriage foes concede they’re losing the war: Adam Serwer notes a constant thread through the last two days of SCOTUS hearings: Opponents of gay marriage repeatedly conceded that public opinion is shifting inexorably in favor of marriage equality. This was meant as an argument against SCOTUS hastening the process, but it actually serves as an acknowledgement that the only remaining question is whether SCOTUS will merely delay the inevitable.

* Citizens United and the war over guns: Can liberals be supportive of Mayor Michael Bloomberg’s big-money ads pressuring Senators on guns, while also opposing Citizens United? As E.J. Dionne notes, those who hope to diminish the influence of big money in politics don’t need to unilaterally disarm themselves while simultaneously battling to end that influence:

Until Citizens United is overturned, as it should be, the best way out of our dilemma is to democratize the money game. So, yes, let’s cheer for Mike Bloomberg. But let’s also insist on creating a system in which we will no longer need his money.

* A bit of discouraging economic news: After a string of decent news on the employment front, jobless claims have hit a discouraging bump. Steve Benen has it in chart form.

* Roberts’ shot at Obama: Also during oral arguments, Roberts took a swipe at Obama, arguing that if he really believes DOMA is unconstitutional, his administration should stop executing the law, rather than merely stop defending it in court. But Politico points out that Roberts himself failed to defend a law as George H.W. Bush’s acting solicitor general, though the parallels are far from perfect.

* And is abortion heading back to the Supreme Court? Andrew Rosenthal argues persuasively that new state level initiatives banning abortion are explicitly designed to force the issue back to the Supreme Court for a rehearing of Roe v. Wade, and that they very well may succeed. And you thought this week’s hearings were contentious…

What else?

Greg Sargent writes The Plum Line blog, a reported opinion blog with a liberal slant -- what you might call “opinionated reporting” from the left.