expatbrit,
Yes. It only becomes illegal if they start calling for specific acts to be done against someone. You cannot discuss the upcoming muder of someone and get away with it. You can, however, call down evil on all redheads and say they all deserve death. You can also get up on a soapbox in the town park and loudly proclaim death to everyone who wears green hats. But you may NOT point to someone with a green hat and say, "I'm gonna kill him right now!"