While the intention may be for foreign countries to pay these tariffs, input tariffs often make life more difficult for domestic manufacturers. This is what makes President Trump's approach to tariffs so unpredictable and potentially dangerous to the U.S. economy and stock market.

The past few weeks have been tough for investors. All three major benchmarks have dropped, temporarily halting what looked like unstoppable momentum.

While tariffs shock investors into risk-off mode, markets are also questioning other parts of Trump's agenda that were meant to be a boost to stocks.