By Kevin Maguire Trade unionist Davie Cooper, a leader of the Upper Clyde Shipbuilders work-in that defeated Ted Heath’s 1971 government, has died aged 84. A union convenor at the Govan yard and avowed Communist, Cooper was a powerful figure behind the scenes when the limelight fell on the likes of Jimmy Reid and Sammy Gilmore. Saving the 8,000 shipbuilders jobs by forcing Tory Heath into a U-turn was one of the labour movement’s most momentous victories. Cooper was influential in enforcing the innovative work-in, workers turning up every day to defy closures. They were under union orders to f…