"We shouldn't let the left-wing pass Hate laws, PC Codes, etc, and decide what words should or shouldn't be used in public discourse."
They are doing so as we speak. Just a couple of examples:
FL Legislator Wants To Outlaw The Term "Illegal Alien" | Sweetness & Light
http://www.sweetness-light.com/archive/florida-legislator-wants-to-outlaw-the-term-illegal-alien
New York City Declares The N-word Off Limits For All | Sweetness & Light
http://www.sweetness-light.com/archive/new-york-city-declares-the-n-word-verbotten
And, of course, that was the point of Coulter's joke.