Well, sort of. With ANY law, if all that is done is to make something illegal, nothing is accomplished (except maybe fooling people into voting for the politician).

There are at least three basic elements which are required, in order to make a law do what it's supposed to.

1) the law itself;

2) enabling laws and regulations to make it POSSIBLE to enforce it;

3) funding.

Complaining that we have enough laws, therefore isn't always or even often, accurate.
A lot of the time, what we need are some additional related laws, to make it POSSIBLE to enforce the first one.

That's the case with too may of the laws which were supposed to allow gun sellers to be responsible players. If we pass a law to require background checks, but then prevent sellers from accessing the data in a reasonable time, the law wont be enforceable. And if no additional funding is provided, even a correctly written law, with appropriate structural support wont be enforced.