Fairly confident, if only because we already do it, and don't seem to suffer for it. I want to emphasize that I'm not advocating the suppression of research, bu

Fairly confident, if only because we already do it, and don't seem to suffer for it. I want to emphasize that I'm not advocating the suppression of research, but of demonstrably false and harmful claims. That is something that exists and is a fairly narrow test. Arguing for healthy people to not receive vaccines definitely falls into this category. It not only harms the people who don't get them it harms the rest of us as well. In fact, I would say the expectation exists that the government will do that. We have come to take for granted that the products we buy are safe and the claims we see are true, precisely because we accept that it's reasonable to expect speech to be limited in this way. Regardless, I don't want to lose the thread. Anti-vaccination is not a commercial enterprise, no one is making false claims and selling them (well, some people are, but not as a product). The example was fair, and I can acknowledge that I may be wrong on that. But I stand by that we can, and should, be allowed to limit speech to prevent harm, just like we limit all sorts of other things for the same reason, including things that are constitutionally protected.