The international aircraft manufacturer Boeing Co. (BA) has announced that it would build its first factory outside of the US. The new factory will be located in China.

The machinists union (which represents 35,000 Boeing workers) is furious. They claim that the new plant will cost US jobs. Their vitriol against Boeing’s decision comes just as the China’s President Xi Jinping is visiting Seattle (Boeing is based in Washington).

“It’s a tough pill to swallow to see our jobs being used as bargaining chips to win orders when we gave up so much for supposed job security,” said Jon Holden, president of the International Association of Machinists District 751.

“This is not simply about China,” he said. “The company is creating capacity and capability outside the Puget Sound region. Those are our jobs.”

Boeing was recently awarded $8.7 billion in tax incentives to continue locating work in Washington. However, there were no clear targets set for the number of jobs Boeing had to keep in state. Moreover, part of the agreement stipulated that machinists would receive a contract extension that ended their pension contributions.

Boeing wishes to open a factory in China in order to better compete with its rival Airbus. Both are struggling to dominate the fast growing Chinese market. Over $1trillion in new planes will be needed over the next 20 years to meet the rising Chinese demand. A local plant will help Boeing to secure new orders.

Boeing executives have been quick to try and quell the fires set by the unionists. Two different press conferences were held on Tuesday in which top executives of Boeing tried to assure Seattle that opening a plant in China would benefit everyone.

“We are in important discussions with Chinese partners about our strategic partnership in China and also possible sales agreements,” said Boeing Commercial Airplanes Chief Executive Ray Conner. “These discussions are at a sensitive stage, and I appreciate your support as we finalize what I hope will be a win for Boeing.”

“I want to assure you that agreements we may reach with our Chinese partners will not result in layoffs or reduce employment for the 737 program in Washington state,” said Conner.

“The model here is global collaboration that allows us to grow jobs in the U.S. and deepen our presence in China,” said Boeing Chief Executive Dennis Muilenburg.

Yet despite these reassuring words, the unions are still not backing down.

“We’ll do everything we can legally and legislatively to protect our jobs,” said Holden.