Sign at a demonstration by students in Plantation, Fla., February 21, 2018. (Carlos Garcia Rawlins/Reuters)

It’s not a ban, and it’s not the answer to mass shootings.

It’s back. In the aftermath of the Parkland, Fla., school massacre, House Democrats are making another attempt at banning so-called assault weapons. A “supermajority” (156 of 193) of House Democrats have signed on, leaving no doubt as to the party’s move left on gun control. The bill, called the “Assault Weapons ban of 2018,” is a non-starter — at least so long as Republicans control the House — but it’s a mistake to simply write off any proposal backed so overwhelmingly by one side of the aisle. This debate isn’t going away.

So let’s deal with he bill on the merits, beginning with taking on its inherently deceptive name. The bill calls for a “ban” on both “semi-automatic assault weapons” and “large capacity magazine feeding devices” (magazines holding more than ten rounds). But then — in the very next paragraphs — it exempts every single weapon and magazine lawfully possessed before the enactment of the law.

In other words, the assault-weapons ban isn’t a ban at all. It would leave tens of millions of guns and magazines on the streets. In fact, nobody actually knows the number. Rifle sales have skyrocketed. Counting rifles made and distributed in the U.S. only (in other words, not counting imports), the number has increased from 1.6 million in 2007 to 4.2 million in 2016. During that time, the AR-15 has been among the most popular rifles sold in the U.S.

In other words, even if the proposed “ban” were enacted, a person who wanted an AR-15 could find an AR-15. A person who wanted a large-capacity magazine could find a large-capacity magazine.

Moreover, the phrase “assault weapons” is also inherently deceptive. The drafters include within the definition not just the scary-looking, military-style rifles such as the AR-15 but also semi-automatic pistols that can “accept a detachable magazine” and have at least one common additional feature such as a threaded barrel. The proposed ban also includes semi-automatic shotguns with, among other things, a pistol grip, a fixed magazine that accepts more than five rounds, or the ability to accept a detachable magazine of any size.

This is the worst kind of gun control. Any measure that preserves the ability of criminals to access guns while restricting the access of law-abiding Americans is a measure that fundamentally impairs the very purpose of the Second Amendment. For the law-abiding, the existing stock of tens (hundreds?) of millions of weapons and magazines would instantly become more expensive. Yet with the slightest premeditation, a criminal could easily circumvent the ban. It’s a simple matter, in fact, to make your own high-capacity magazine.

Moreover, it’s sheer speculation that a ban on so-called assault weapons would reduce mass shootings, reduce gun suicides, or reduce overall gun violence. Rifles are rarely used in “normal” gun crimes (blunt objects and fists kill more people), and you don’t need an AR-15 to kill yourself (rifle suicides are rare). And as ample, grim experience shows, you don’t need an AR-15 to commit a horrific mass killing. America’s worst school shooting — the Virginia Tech massacre — was committed with handguns, and the list of deadly handgun shootings is long and sad.

Mass shooters are among the most committed criminals in the entire United States. They often fantasize about their attacks for years and plan them for months. They can find an AR-15. Yet an AR-15 isn’t an indispensable weapon for a spree killer. They have options.

At best, then, the argument is that making an AR-15 slightly more difficult to obtain won’t make spree killings less common, but it might make spree killings less lethal. Again, that’s more speculation, assuming that the most committed killers 1) can’t get their hands one of the tens of millions of legal weapons still on the streets; and 2) that a man with a semi-automatic pistol isn’t just as deadly as a man with a rifle. Neither assumption is warranted.

In fact, experience with the previous federal assault-weapons ban demonstrates that any benefit gained by decrease in crimes committed with one type of weapon is often offset by increases in crimes committed with other weapons, leaving no net benefit. Here’s the key language from a comprehensive study of the impact of the federal assault-weapons ban:

We cannot clearly credit the ban with any of the nation’s recent drop in gun violence. And, indeed, there has been no discernible reduction in the lethality and injuriousness of gun violence, based on indicators like the percentage of gun crimes resulting in death or the share of gunfire incidents resulting in injury, as we might have expected had the ban reduced crimes with both AW [assault weapons] and LCMs [large-capacity magazines].

And that study is based on a world where tens of millions fewer assault magazines and large-capacity magazines were in circulation. The facts on the ground have changed, substantially, since 2004.

Police officers need 15 rounds in a pistol to defend themselves, but I don’t need 15 rounds to defend myself? How is that coherent?

But we have to offset the known and undeniable negatives against the entirely speculative positive effect. Millions of law-abiding Americans would find it more difficult to obtain guns and magazines that would match the foreseeable criminal threat. Indeed, the necessity of assault weapons and large-capacity magazines to confront the criminal threat is illustrated by the proposed ban itself, which exempts law-enforcement officers. Police officers need 15 rounds in a pistol to defend themselves, but I don’t need 15 rounds to defend myself? How is that coherent?

An assault-weapons non-ban does nothing to address the underlying causes of mass shootings. It does nothing to empower citizens or police to respond to troubled individuals before they pull the trigger, and it does nothing to enhance the ability of citizens to defend themselves once engaged. In fact, it may well put the armed citizen at a meaningful disadvantage. It’s not the answer to mass killings. It’s not even “an” answer. It is, however, an infringement on individual liberty, and it’s one that a majority of American voters will not tolerate.