Eagan-based Northwest airlines is launching a campaign to convince union leaders of the need to reduce labor costs. Company officials have told Wall Street they need to cut overall expenses by as much as a billion and a half dollars. Northwest has already cut almost 12 thousand jobs and more than a billion dollars in expenses in about 2 years. But labor leaders at the nation's fourth largest airline say the last round of concessions has bred strong resistance to another round of give-backs. Minnesota Public Radio's Bill Catlin reports.