Wel, I guess it's time to delve into semantics.
What I call 'censorship' is when the government says, hey, you are not allowed to sell that. There IS censorship in America, nobody is allowed to sell child porn, and bestiality is illegal in many states. That's really the extent of it. There may be things you can buy in other places that you can't buy here, but I don't believe that is due to censorship. See my previous post regarding the marketability of such items.
When the government says, you have to put your magazines in plastic bags with black rectangles on certain areas, I do not call that censorship for two important reasons:
1) You are still allowed to sell it
2) I am still allowed to buy it
There are rules the government sets in place on how those items can be publically displayed; this does not fit my view for censorship.
You also have to realize that cities DO have the right to make local laws that seem to overstep federal guidelines.
For example: A new strip club (titty bar, whatever you want to call it) opened up in a suburb near me. The city council immediately voted to ban all types of adult entertainment within city limits. Now, they could not stop the place that was already open, but they can prohibit other places from opening. Larry Flint's lawer came to town, crying censorship, and filed a lawsuit in federal court. When it finally went before the judge he deliberated for about a half an hour and told them, too bad, the law stands. (Ironically, the bar was shut down because of gross liquor law violations, and went up for sale soon after.)
The point is, if a group of people in a city get together and pass a law for the common good of those people, it will stand. We can outlaw all porn altogether, or we can allow all forms of it. To say that the government censors porn is really not a wholly accurate description.
Nobody yet has told me who censors porn in the US and what the laws are concerning porn. Yet you still claim censorship based on your experiences.