We are all familiar with the division of liberties and rights into "negative" and "positive." A negative right is the kind of right that doesn't require anyone to provide you with anything; it just forbids them from interfering with you. A positive right requires some actual provision. In Georgia as in several other states, for example, there is a positive right in the state constitution to hunt and to fish. This means that the state is obligated to provide the means for such hunting and fishing. It cannot be the case that you have a positive right to hunt, but that there is no land available on which you may exercise this right. If you have a positive right to fish, you must have access to at least some waters in which fishing is possible.
These rights aren't unfettered -- there are licensing requirements, fees, bag limits, and so forth -- but they do require that the state provide something for you. Your right imposes an obligation on the state not merely to refrain, but to act on your behalf to secure the thing to which you have a right.
All that is well understood. However, what is less well understood is that there is a middle ground between the two categories. There are some otherwise-negative rights that require physical goods. No one is obligated to provide you with these goods, but your right to provide yourself with them is protected. Thus, the Second Amendment says that the right to keep and bear arms shall not be infringed. Nobody needs to provide you with arms, but you must not be stopped from purchasing your own if you desire.
But it's a little stronger than that. There is an almost-positive element to it: we are obligated not to try to make the arms unavailable. It won't do to set up a case in which anyone who wishes to buy a firearm can buy one, but there are none to buy. It won't do for a governor to say, "I'm not infringing your right; go buy a gun, any gun you can find!" if that governor has previously arranged to buy up all the guns and melt them down.
In such a case the negative right has ceased to exist even though it is allegedly still extant and uninfringed by any letter of law. There isn't a positive right as such, but there almost is: the government may not be legally obligated to provide the good, or even access to the good. Yet if it isn't obligated not to prevent the possibility of access to the good, the right can cease to exist as an actual right that you can really exercise.
A similar case occurs with these "Free Speech zones," whereby the government orders you not to engage in assembly or speech near a political convention (say), except in a narrow area too small for all the competing groups (and usually far from the actual event). You have a negative right that is technically not being infringed; and technically, there is even a place provided for its exercise. But practically, the right is denied if there is not a place in which to practice it.
So yesterday I wrote up a piece about Commerce, Georgia, and the public pool that does not permit cursing. Is that an unacceptable infringement of freedom of speech, for the government officials who run the pool to refuse to allow you to speak certain words in a public park? Perhaps not, if you think that the existence of the rest of the world is an adequate amount of space for cursing in; in that case, you could say that this is better, because we have one place for people who don't like to hear foul language (and do like to swim), and people who like to curse can go do it elsewhere when they are done swimming; or they can simply forgo swimming, and curse all day if it pleases them.
How far can we take that principle? Can we ban cursing on all public property? Within the city limits, whether the land is public or private? Within the county? Within a state? Within the United States? At some point we're crossing that line pertaining to the mostly-negative right that has a necessary physical component. Just where?