GZ may or may not need permission. Most FR posts take excerpts from copyright material. This is conditionally legal - and the source can sometimes but not always change the conditions by complaining. The doctrine is called fair use, and the rules can get quite complicated. Using a small excerpt for the purpose of commentary is generally permitted unless the copyright holder specifies otherwise. parody has even broader rules with less recourse for the copyright holder, and Zimmerman may win under freedom of expression, since he modified copyright work for the purpose of political commentary, which is the application with the loosest restrictions on fair use. Only the courts can answer this question in this case, but I think it's on the borderline with a slight edge for GZ.
See my post above. I think it is safely across a clear bright line.
I think George is going to lose royally.