A trade war with China could be very bad news for some of America's largest companies. Apple (AAPL) generated $18 billion in revenue -- 20% of its total sales -- from China in just its most recent quarter. Boeing's (BA) China sales last year were nearly $12 billion, almost 13% of its overall revenue. Related: China says it will hit back if US announces new tariffsBut the growth of the middle class in China has helped other big US companies too. Post-It and Scotch Magic Tape maker 3M (MMM), also in the Dow, generated 10% of its sales from China last year too.

Source: CNN March 22, 2018 17:49 UTC