The part that worries me even more than the death threats was the classification of the Occupy movement as 'terrorist activity'. This opens them up to a whole catalogue of surveillance methods and methods of detention, and is a good illustration of terrorism powers being extended and misused for domestic dissent.
This misuse of the label 'terrorist' highlights the danger of employing extra-legal means to attack your enemies in other countries, it undermines the rule of law everywhere, and weakens the accountability of all law enforcement agencies. Assassination, torture, rendition, and detention without trial are all normalised now in the US for terrorists. The definition of an enemy for the state always includes some of its citizens, so you end up with scope creep where formerly completely illegal and unthinkable acts are considered normal, just because the word terrorism has been used in conjunction with a person or organisation.