Perfection is a lie and asking for it is disingenuous.
No one ever asked for a law that would prevent every car death. We just saw the opportunity to prevent hundreds of millions of deaths with car seats, and we did it.
The same is true for guns. One law will never be the answer. It has to be a suite of laws with community involvement, similar to every other country in the world but modified to the US context. I give several examples in this article of laws that have been effective elsewhere.