Boeing Co machinists soundly rejected an eight-year labor contract extension on Wednesday that would have let them build the company’s newest jetliner in Washington, a historic decision that could forever alter the course of Boeing’s 97-year presence in the state. International Association of Machinists members voted 67 percent against a deal that would secure an estimated 20 years of work building Boeing’s 777X jet, but a deal that would have terminated their pension plan and raised their healthcare costs. The decision means Boeing will consider building key parts of the 777X, including the wings, in non-union U.S. states or in Japan, where it has already received an offer. A crowd of more than 100 people erupted in cheers when the vote was announced amid a charged atmosphere at the union’s main hall in Seattle.