From the Summary on the U.S.-China Economic and Security Review Commission website: "China's direct financial linkages with the United States have been growing but remain very modest when compared to the two countries' trade linkages. Beijing has taken steps to gradually open its financial sector to foreign investors, but U.S. investors have displayed little interest since the reforms are happening as Chinese policymakers impose tighter restrictions on foreign currency conversions and outbound capital flows. Economic and financial developments in China can affect U.S. financial markets more substantially through indirect channels, as was evident in the reaction of U.S. equities to China's stock market crashes in 2015 and 2016. More broadly, the impact of China's slowing growth and economic reforms on trade, commodities demand, and investor confidence affects global financial markets, which in turn influence U.S. financial markets."
U.S.-China Economic and Security Review Commission: http://www.uscc.gov/