Commentary by a Jefferies analyst illustrates that commitments to buy the company’s jets could be a negotiating chip in the trade war.

Key Takeaways Boeing shares plunged Friday as markets continued the slide sparked by the Trump administration's new tariffs.China on Friday said it would match the new 34% U.S. tariff on American products imported into the country.

Boeing (NYSE:BA) -8.3% in Friday's trading to a two-and-half year low, as markets continue to slide in response to the Trump administration's latest tariffs and China's retaliation that would match the new 34% U.