Boeing executives extended an olive branch to the company's strained supply chain this week to help them deal with the fallout of the latest 737 MAX crisis, but those firms are taking a wait-and-see attitude after years of dealing with the planemaker's hard-line approach. The aerospace giant's shift in tone was underlined by a speech on Wednesday by Ihssane Mounir, Boeing's vice president of supply chain and fabrication, at an aerospace conference outside Seattle. Mounir's remarks - and those of Boeing's head of supplier quality on Tuesday - were the first public addresses by Boeing to its base of more than 1,100 suppliers in the Pacific Northwest region after a Jan. 5 mid-air blowout on a Boeing 737 MAX 9 that has rocked the aerospace industry.