Air Force One. It was firing one across the bow.
China has been wooing Boeing to open a manufacturing plant in China, but not for the labor force. No, it was so they could gleen technology and trade secrets in order to further their own interests in aeronautics.
Trump addressed this in the debates. Globalists are all for the global economy even if it means the loss of US jobs, technology and trade secrets.
https://theconservativetreehouse.com/2016/12/06/trump-economics-today-delivering-a-handshake-and-a-warning/#more-125437