On every corner a terrorist, hoodie, or scientologist could be lurking, ready to ruin someone's perfectly pleasant day.
So when last week a policeman swept bravely upon Golley Slater's new head of social media, Stephen Fitzpatrick, an industry collectively held its breath. What terror had Fitzpatrick been unleashing?
The Finchley Met Bobby takes up the story: 'The suspect was doing Tai Chi in the bushes in the corner of an open public area. I stopped Mr Fitzpatrick to ask what he was doing and also for any anti-social behaviour (sic).'
Tai Chi is the art of moving like the martial arts film star Bruce Lee in slow motion. Fitzpatrick is advising an online PR campaign for the website energyarts.com, which aims to spread the word about Tai Chi's health benefits. One of them, presumably, is that the attention of the local constabulary will get the heart rate moving along a little bit faster.