Who is Ian from Sarah Kane: Complete Plays and what is their importance?

In "Blasted", Ian is a racist, middle-aged tabloid journalist. He is divorced and has a teenage son named Mathew. He implies throughout the play that he does clandestine work from the British government, including delivering messages, overseeing mass burials, and even killing. Ian had an affair with the mentally challenged Cate when she was in her teens.