Quite honestly the thing I find most deeply offensive about this move is the gratuitous stupidity of it.

Who believes terrorists would post their intentions on twitter? and even if they did, all they need to do to avoid this ridiculous farce is swap out a word: psst 'engage in revelry' = 'destroy'

There is no trade off between security and freedom taking place here, there is just a parody acting out that not only fails to make anybody any safer, it causes all reasonable people to blanch in shame.