comment: Firstly, if no material harm is done these things aren't illegal in the USA.  You can't paint a swastika over the sickle and hammer if it's someone else's property that has them displayed, but you can paint it if you have the rights to paint anything in that location.  You can certainly make a cookbook for human meat (the cannibal cookbook is available not only in hardcover, but now in paperback.
  You cannot incite immediate violence of course, but on face you seem to be arguing for change to what amounts the unchanged status quo.
  Then...if you extend this to just not responding to things that you don't like that itself is a massive limitation on expression.  The swastika itself is a statement against the status quo - a response to something already being said.  Yet...you'd allow that response but then want us to stop after that?  How does this work?  A pride parade is a response in some ways to bigotry expressed by others.  Should we not have pride parades because hatred was first uttered by the homophobes?