Charlie Sykes, who, during the Tea Party summer said it was the right of Americans to tell their politicians to go to hell, spent the morning whipping his listeners into a froth that protesters would march in Scott Walker's neighborhood and pass his house. "Targeting private family homes." The wildly unpopular Walker, prompted by Sykes, said this tactic is "crossing the line." (the relevant part of the unfortunate exchange starts around 20:50). To top it off, he made a Gabby Giffords reference.
The Supreme Court, including Scalia, would disagree that it crosses a line.
"Although the town's streets are narrow and of a residential character, they are nevertheless traditional public fora ..."