While there are a few concerns that have investors' attention at the moment, including a forecasted contraction in first-quarter gross domestic product, along with the historic priciness of stocks, perhaps the prevailing issue for the stock market is President Donald Trump's tariff policy.

The S&P 500 (SNPINDEX: ^GSPC) has declined 7% from its high as the Trump administration has imposed tariffs on goods from several countries. The president has also outlined plans for more aggressive reciprocal tariffs scheduled to take effect on April 2.