New British Prime Minister Andy Burnham set out a sweeping political vision on Tuesday, pledging to give Britain “a new social contract for the 21st century”, reform the country’s electoral system and reset its relationship with its European neighbours. But he acknowledged that economic constraints make delivering his sweeping plans a big political risk. “Small things will not get us through what are difficult times,” Burnham said in a tough-love speech to the centre-left Labour Party’s annual...