smacky and bucky

Pat Robertson is apparently allowed to say the US government should assassinate the president of Venezuela. On the other hand, a tabloid newspaper in England had to apologize and pay damages to Justin Timberlake for printing a story saying he had an affair. What's wrong with these two stories?

Does this mean if someone prints an editorial in that same paper saying the US government should kill Justin Timberlake, then that's fine?

(I can imagine the search terms leading to this post...)