assuming everything else unchanged ( that is we don't consider any other things here).
China (and many their countries), run trade surpluses by lowering its currency and use their earned new money from trade to buy U.S. dollars, U.S. bonds, and even U.S. stocks, therefore contributing to the stock market booming. If this trade surpluses reduced because of the increased u.s. exports or reduced Chinese import or both, there would be less money inflow to U.S. dollar, bonds and stocks. The market would go lower in response to this change.
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