Welcome to China, Boeing!   Finally, this American based aircraft maker going to China. This will be Boeing's first overseas airliner assembly plant in China. Based on its business deal, Boeing also will sell 300 new aircrafts to three Chinese companies.     Yet, Boeing has not issued a statement. Nor has the International Association of Machinists and Aerospace Workers, the union that represents more than 33,000 workers at the company’s longtime manufacturing ba...