TORONTO (Reuters) – Western countries should have a united front against China to prevent the Asian state from using commercial interests to play them against each other, Canadian Prime Minister Justin Trudeau said in an interview aired on Saturday. Trudeau said China has been “playing” Western countries against one another as they compete for access to economic opportunities in the country. “We’ve been competing and China has been, from time to time, very cleverly playing us off each other in an open market, competitive way,” he said in an interview with Global television. “We need to do a be…