Assault weapons are still being sold.
Lawmakers may outlaw certain types of weapons, but they may not disarm the citizenry. The "right to bear arms" is not a right to nullify any government measure a resident may find objectionable.
The Second Amendment Is Not Absolute
Constitutional rights are not absolute. They never have been and, practically, never can be. In our constitutional democracy, we have always recognized that we can, and must, have our constitutional cake and regulate it too.
The Second Amendment, of course, is no exception. In the 2008 case of District of Columbia v. Heller, the Supreme Court told us that we have a constitutional right to possess firearms for self-defense, at least within our homes. But the opinion never suggested that this right was unconditional or immune from all regulation. In fact, Justice Scalia, writing for the majority, said just the opposite. In Heller, he specifically said that “the right secured by the Second Amendment is not unlimited.”
Protecting the right to keep and bear arms is not the same as forbidding all regulations on that right. We can protect that right and still require background checks, permits, and training. We can still regulate when, where, and what kinds of guns are allowed. In some cases, we can regulate who can obtain guns, imposing restrictions on, for instance, felons, the mentally ill, and known terrorists. We can ban firearms such as military-style assault weapons that (like child pornography) plainly cause far more harm than they add in value. We can require those who are negligent with their weapons (as we do those who are negligent with their words in defamation cases) to be held liable for the harm they inflict on others. We can do all of these things; we just don’t. There might be policy reasons to debate the pros and cons of specific regulations, but there’s no reason to assume that there is a constitutional problem.