From the Wall Street Journal Editorials,  About That Obama Boom:

A closing word to Trumpians who will point to the fourth-quarter decline in net exports that subtracted 1.7% from GDP. Part of the explanation is that a bumper crop of soybean exports boosted growth in the third quarter and then dropped off at the end of the year. This is not an argument for starting a trade war with China or Mexico, which could harm U.S. exports.

Imports are subtracted from GDP calculations to avoid overstating domestic production, but that doesn’t mean the U.S. should ban imports or run a trade surplus. Imports are vital to American prosperity, both as components for exports and affordable goods for consumers. They enhance the U.S. standard of living. Mr. Trump should keep his policy focus on growth, not on the meaningless trade balance.