A freezing winter of discontent, a Labour party hell-bent on making itself unelectable, controversial warmongering and record levels of inequality. It may sound like yesterday’s papers but these themes were also addressed by iconoclastic post-punk artrockers Gang of Four in the late Seventies and early Eighties, more than 10 years before the Manics brought agit rock to the masses. Next Monday Gang of Four release Content, their first original album in 16 years.