text:  Conservatives have sought this outcome for years, and liberals now worry the ruling could affect thousands of cases in which federal regulators prevailed. ABC's Stephen Portnoy. Canada's second largest airline has canceled more than 400 flights, affecting nearly 50,000 travelers amid a labor strike. Maintenance workers at WestJet have gone on strike following two weeks of turbulent discussions with the airline on a new labor contract, the strike affecting both domestic and international flights. I'm Mark Remillard, ABC News.