Editor's note: Paul Waldman is a contributing editor at The American Prospect and the author of "Being Right Is Not Enough: What Progressives Must Learn From Conservative Success." Follow him on his blog and on Twitter.
(CNN) -- When the Manchin-Toomey background check amendment, a modest gun restriction by any reasonable measure, was defeated, President Barack Obama called it a "shameful day in Washington." But as anyone who watches Congress knows, it has more than its share of shameful days.
There the deck was stacked against not only this bill, but against any bill that would restrict the proliferation of guns in any way. If those seeking sanity in our gun laws want to succeed, they'd better prepare themselves for a difficult journey.
Many people thought that the Newtown massacre changed everything about the gun debate in America, and that new legislation was inevitable. The first part of that belief is still true; the second part is not. The bill was doomed for a number of reasons.
The Senate is an extraordinarily undemocratic institution, where outsized power goes to the small, rural states with strong support for unlimited gun rights. The 57 million Americans who live in California and New York get four votes in the Senate, all of which were in favor of background checks.
But the 1.3 million Americans who live in Wyoming and North Dakota also get four votes, and they were all opposed. And that's not to mention the filibuster, which allows the minority to thwart the majority's will. You might not have realized it if you watched the coverage, but this background check bill was supported by a majority of the Senate.
And even if it had passed the Senate, the bill would have likely died in the House, which is tilted in favor of Republicans, mostly because the way Americans are distributed. More Americans voted for Democrats than Republicans in the 2012 House elections, but Republicans enjoy a 31-seat advantage, meaning their leader controls the agenda and can kill any bill he and his caucus dislike.
So does this mean the NRA still inspires the same fear it long has among lawmakers? Not really.
The truth is that most of the people who threatened to filibuster the background check bill aren't afraid of the NRA. They're on its side. They don't need to be intimidated or even persuaded.
Take Sen. Chuck Grassley of Iowa, who many years ago was known as a straightforward, even moderate fellow, but who at some point decided that if he didn't like a bill, the best thing to do is to simply lie about what it contained, stoke fears or both.
He did it when he spread the "death panel" lie during the debate over health reform, and he did it again this time, telling people falsely that the Manchin-Toomey amendment would mean a national registry of every American who owns a gun. He then warned darkly, "when registration fails, the next move will be gun confiscation."
For the record, the Manchin-Toomey amendment specifically forbade the government from creating a gun registry, which is why Obama and Sen. Joe Manchin of West Virginia -- a guy from a state Obama lost by 27 points in 2012, who got elected to the Senate with an ad showing him firing a rifle shot through a piece of legislation while the announcer trumpeted his NRA endorsement -- accused the NRA and its supporters of lying about it.
But Grassley and others spread the lie, knowing it would energize the paranoid and influence the more cowardly of their colleagues. As one gun lobbyist gloated after the bill was defeated, "The gun registry defined the battle over universal background checks."
We shouldn't have been too surprised.
But one of the salutary effects of this debate is how it has brought to wider public attention the kind of unhinged conspiracy theorizing, paranoia and outright hate most Americans wouldn't know about if they hadn't been attending NRA meetings or reading pro-gun Web sites in recent years.
The insanity of some of those who opposed this bill was captured by the Minnesota radio host who said to the Newtown families, "I'm sorry that you suffered a tragedy, but you know what? Deal with it, and don't force me to lose my liberty, which is a greater tragedy than your loss."
That's right -- having to get a background check when you buy a gun at a gun show is worse than having your child murdered. For good measure, he added that if he had the opportunity to meet those families, "I would stand in front of them and tell them, 'Go to hell.' "
Most gun owners would hear that and be disgusted, just as most gun owners think universal background checks are perfectly reasonable. So now, gun safety advocates have to change how they think of their cause. It would have been nice if we could have made our gun laws a little more sane in this first try, but sometimes, change takes longer. But change is already underway.
For 15 years, the debate on guns in America was no debate at all.
One side would scream, "They're coming for your guns!" and the other side would respond, "Can't we talk about something else?"
Now we actually have a debate with two sides. Democratic politicians (and a few Republicans) are no longer so afraid to say that the right to bear arms is not infinite; like every other right in the Constitution, it's subject to reasonable limits.
The money from the gun manufacturers and the NRA will be met with an equally well-funded campaign -- and maybe more well-funded -- from Michael Bloomberg.
In fact, this defeat may be just what the gun safety movement needs to energize its supporters.
Talk to liberals a day after the vote, and you'll hear anger, frustration and disgust at the craven senators who couldn't stand up to the gun lobby. Those emotions are exactly what spur people to become involved. If they want to succeed, in the coming months and years, they'll need to make sure their voices are as loud as those of the NRA and its supporters.
A number on a poll, like the 90% of Americans who support universal background checks, isn't politically meaningful unless it inspires some fear in lawmakers.
This time around, they obviously weren't afraid enough. But if support for new gun measures can become an actual movement again -- with letters and phone calls and contributions and door knocking and an unmistakable message to candidates that there will be a price to be paid for going against it -- then next time around, they may be.
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The opinions expressed in this commentary are solely those of Paul Waldman.