When I appeared on CNN’s Piers Morgan Tonight to debate gun control on Thursday night, I came armed with a copy of the Constitution of the United States.

I did so for a very simple reason: for too long, the left has been getting away with the lie that they are pro-Second Amendment. Then they proceed to violate the most basic concept of the Second Amendment: that we have a right to keep and bear arms. It is fine to have a rational conversation about how to balance rights with the risk and rewards of particular firearm ownership. But that is not what the left does. They loudly proclaim support for the right to bear arms but then ask, “Why should you be allowed to keep an AR-15 in your home?”

The left pretends it is for the Second Amendment because it recognizes that the American public likes the Second Amendment. But the left has no real defense for the Second Amendment on a philosophical level. They say that they want assault weapons gone, as Piers Morgan does, in order to prevent gun death. But then they say that they’re fine with handgun ownership, which is the instrument used in exponentially more gun death. They can’t explain this mental gymnastics. When I asked Morgan about it, he replied, “We’ll come to that.” He never did.

Here’s the truth. Ideally, the left wants to ban all guns. They just aren’t willing to go there yet, because they know it’s politically unpalatable.

How do we know that? Because that’s what Piers Morgan said the other night with me. First, he claimed he loved the Second Amendment. “I believe and respect an American’s, under the second amendment of the Constitution – that you kindly brought in – to defend themselves with a handgun or a pistol.” But when I explained to Morgan just why the Second Amendment was enshrined into law – in order to prevent the threat of foreign invasion and domestic usurpation – he balked and said that such an argument was absurd.

So he was for the Second Amendment; he just couldn’t explain why.

Which means he was really against it, as he showed seconds later. First, angry at me for having failed to bow to a bevy of rhetorical gambits culminating in a lackluster attempt to browbeat me with an old letter of Ronald Reagan’s, Morgan grabbed the copy of the Constitution I’d brought. Waving it my face, he nearly shouted, “You come in, you brandish your little book -“

For just a moment, the mask slipped. To Morgan, the Constitution was nothing more than a little book, not the single most important document in American history and the basis for the freest and most powerful nation in world history. It wasn’t a document to which politicians swear allegiance and for which American soldiers shed blood. It was a little book, an annoyance in the way of his all-compassionate perspective on gun control.

But it wasn’t just a Freudian slip. He refused to admit to me that he wanted a total gun ban. Then, once I was safely off the set, he turned to another guest, Tony Robbins, and whined: “What is hard is when I’m categorized as being this raging lefty who hates the Constitution. You know, I totally respect and admire the Constitution and the Second Amendment and Americans’ right to defend themselves at home… In an ideal world, I’d have all the guns gone, as we have in Britain, but this is not my country, and I respect the fact that most Americans wouldn’t wear that kind of argument.”

In other words, Piers likes the Second Amendment because he has to, but if he had his druthers, it would go up in a puff of gunpowder-free smoke.

Unfortunately, Morgan’s perspective on that “little book” is held by wide swaths of the left. President Obama and Vice President Joe Biden seem perfectly happy to continue to use executive power to achieve an imperial presidency in violation of the checks and balances of the Constitution. Democrats in the Senate and House have suggested that Congress abdicate its fundamental duty on the debt ceiling and allow President Obama to unilaterally raise it. And when it comes to the Constitution’s limited powers, the left has hated them for well over a century.

Now, there are parts of the Constitution that the left likes, since the left sees the Constitution as more of a buffet than as a cohesive scheme of government designed by wise men and amended over time. They like the First Amendment but not the Second. They like the parts of the Eighth Amendment (cruel and unusual punishment) but not the Tenth Amendment (powers not delegated to the feds are delegated to the states or the people). The Constitution is not something the left is ideologically or philosophically attached to. It is an inconvenient relic of a bygone age. And, if they had their druthers, as Morgan said, they’d go for broke.

Unfortunately for them, the Constitution stands in their way. So they have sought to pervert the Constitution through the courts, to pretend to be defenders of the Constitution while undermining its fundamental principles.

Enough is enough. For the left, that “little book” is a speed bump on the road to progress. For those on the right, that “little book” remains the greatest embodiment of wisdom about government ever assembled. That is a fundamental debate. And it is a debate we ought to have, rather than pretending that the left has the same basic love for the Constitution as the right.

Ben Shapiro is Editor-At-Large of Breitbart News and author of the book “Bullies: How the Left’s Culture of Fear and Intimidation Silences America” (Threshold Editions, January 8, 2013).