While an independent judiciary is a nice convenience, it is not the sole or even the necessary protection of the First Amendment. The real protection for the First Amendment is the people, as voters and as citizens and if necessary as activists. If we elect representatives and presidents who respect our liberties, we will not need an independent judiciary to protect our rights. If we don't, our "independent" judges, like John Roberts, are not likely to be ones who will stand up for them.
The funny thing, of course, is that by their very decision, the Roberts majority transformed the phrase "Bong Hits 4 Jesus." If I wear a shirt today emblazoned with the slogan, I am not saying a damn thing about drugs. I'm saying to the "independent" judiciary, stop tramping on free speech.