Do you understand what that ruling means? It affords people with no religion the same protection as religions. It does not make atheism a religion.Unfortunately, the founders didn't foresee atheism would be declared a religion by the Supreme Court, and that it would become the de facto religion of the country by default. That's why the First Amendment needs to be amended; to accomodate for that miscalculation.
The true effect of the First Amendment has been "Atheism will be the established religion of the United States". Few Americans would want that. And that's how it needs to be presented to them.