Kingdom come / J.G. Ballard.

Enhanced descriptions from Syndetics:

A violent novel filled with insidious twists, Kingdom Come follows the exploits of Richard Pearson, a rebellious, unemployed advertising executive, whose father is gunned down by a deranged mental patient in a vast shopping mall outside Heathrow Airport. When the prime suspect is released without charge, Richard's suspicions are aroused. Investigating the mystery, Richard uncovers at the Metro-Centre mall a neo-fascist world whose charismatic spokesperson is whipping up the masses into a state of unsustainable frenzy. Riots frequently terrorize the complex, immigrant communities are attacked by hooligans, and sports events mushroom into jingoistic political rallies. In this gripping, dystopian tour de force, J.G. Ballard holds up a mirror to suburban mind rot, revealing the darker forces at work beneath the gloss of consumerism and flag-waving patriotism.