Radio host Pete Santilli issues threats against Hillary and Obama

Does this guy have any responsibility for decency or (gasp) telling the truth? At what point is there a limit to free speech?

Should this type of threat cause the involvement of the FBI? Secret Service?Is there a difference in the rhetoric found here and the obviously bad taste tweet of Lizz Winstead? (tornadoes are targetting conservatives.) Winstead did self correct and admit her timing was horrible and she should have known better. Has Santilli issued any remarks admitting stupidity?